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Sample records for sensory eye dominance

  1. A binocular perimetry study of the causes and implications of sensory eye dominance.

    PubMed

    Xu, Jingping P; He, Zijiang J; Ooi, Teng Leng

    2011-12-01

    Sensory eye dominance (SED) reflects an imbalance of interocular inhibition in the binocular network. Extending an earlier work (Ooi & He, 2001) that measured global SED within the central 6°, the current study measured SED locally at 17 locations within the central 8° of the binocular visual field. The eccentricities (radius) chosen for this, "binocular perimetry", study were 0° (fovea), 2° and 4°. At each eccentricity, eight concentric locations (polar angle: 0°, 45°, 90°, 135°, 180°, 225°, 270°, and 315°) were tested. The outcome, an SED map, sets up comparison between local SED and other visual functions [monocular contrast threshold, binocular disparity threshold, reaction time to detect depth, the dynamics of binocular rivalry and motor eye dominance]. Our analysis shows that an observer's SED varies gradually across the binocular visual field both in its sign and magnitude. The strong eye channel revealed in the SED measurement does not always have a lower monocular contrast threshold, and does not need to be the motor dominant eye. There exists significant correlation between SED and binocular disparity threshold, and between SED and the response time to detect depth of a random-dot stereogram. A significant correlation is also found between SED and the eye that predominates when viewing an extended duration binocular rivalry stimulus. While it is difficult to attribute casual factors based on correlation analyses, these observations agree with the notion that an imbalance of interocular inhibition, which is largely revealed as SED, is a significant factor impeding binocular visual perception. PMID:21989227

  2. A New Method to Assess Eye Dominance

    ERIC Educational Resources Information Center

    Valle-Inclan, Fernando; Blanco, Manuel J.; Soto, David; Leiros, Luz

    2008-01-01

    People usually show a stable preference for one of their eyes when monocular viewing is required ("sighting dominance") or under dichoptic stimulation conditions ("sensory eye-dominance"). Current procedures to assess this "eye dominance" are prone to error. Here we present a new method that provides a continuous measure of eye dominance and…

  3. Sensory afferent segregation in three-eared frogs resemble the dominance columns observed in three-eyed frogs.

    PubMed

    Elliott, Karen L; Houston, Douglas W; Fritzsch, Bernd

    2015-01-01

    The formation of proper sensory afferent connections during development is essential for brain function. Activity-based competition is believed to drive ocular dominance columns (ODC) in mammals and in experimentally-generated three-eyed frogs. ODC formation is thus a compromise of activity differences between two eyes and similar molecular cues. To gauge the generality of graphical map formation in the brain, we investigated the inner ear projection, known for its well-defined and early segregation of afferents from vestibular and auditory endorgans. In analogy to three eyed-frogs, we generated three-eared frogs to assess to what extent vestibular afferents from two adjacent ears could segregate. Donor ears were transplanted either in the native orientation or rotated by 90 degrees. These manipulations should result in either similar or different induced activity between both ears, respectively. Three-eared frogs with normal orientation showed normal swimming whereas those with a rotated third ear showed aberrant behaviors. Projection studies revealed that only afferents from the rotated ears segregated from those from the native ear within the vestibular nucleus, resembling the ocular dominance columns formed in three-eyed frogs. Vestibular segregation suggests that mechanisms comparable to those operating in the ODC formation of the visual system may act on vestibular projection refinements. PMID:25661240

  4. Sensory afferent segregation in three-eared frogs resemble the dominance columns observed in three-eyed frogs

    PubMed Central

    Elliott, Karen L.; Houston, Douglas W.; Fritzsch, Bernd

    2015-01-01

    The formation of proper sensory afferent connections during development is essential for brain function. Activity-based competition is believed to drive ocular dominance columns (ODC) in mammals and in experimentally-generated three-eyed frogs. ODC formation is thus a compromise of activity differences between two eyes and similar molecular cues. To gauge the generality of graphical map formation in the brain, we investigated the inner ear projection, known for its well-defined and early segregation of afferents from vestibular and auditory endorgans. In analogy to three eyed-frogs, we generated three-eared frogs to assess to what extent vestibular afferents from two adjacent ears could segregate. Donor ears were transplanted either in the native orientation or rotated by 90 degrees. These manipulations should result in either similar or different induced activity between both ears, respectively. Three-eared frogs with normal orientation showed normal swimming whereas those with a rotated third ear showed aberrant behaviors. Projection studies revealed that only afferents from the rotated ears segregated from those from the native ear within the vestibular nucleus, resembling the ocular dominance columns formed in three-eyed frogs. Vestibular segregation suggests that mechanisms comparable to those operating in the ODC formation of the visual system may act on vestibular projection refinements. PMID:25661240

  5. Unilateral ptosis and eye dominance.

    PubMed

    Lyon, D B; Gonnering, R S; Dortzbach, R K; Lemke, B N

    1993-12-01

    We studied the relationship between eye dominance (Scobee test) and upper lid level (MRD) in 54 patients with unilateral ptosis or asymmetric bilateral ptosis (> or = 2 mm difference in MRD) using the phenylephrine test. A contralateral lid drop was measured in 12/54 patients after instillation of 2.5% phenylephrine in the more ptotic eye and occurred in both congenital (3) and acquired (9) ptosis cases. A contralateral lid drop was seen in 7/14 (50%) patients whose ptosis was greater in the dominant eye and in 5/40 (12.5%) patients whose ptosis was greater in the nondominant eye (p = .01). Contralateral lid drops > or = 1 mm were present in 7/54 patients, and 6/14 (43%) of them had greater ptosis on the dominant side and 1/40 (2.5%) on the non-dominant side (p = .001). There was no association between contralateral pseudoretraction and either visual acuity or severity of ptosis. These results suggest that levator muscle tone is influenced by eye dominance when ptosis is present. The preoperative evaluation of unilateral or asymmetrical bilateral ptosis cases should include the Scobee and phenylephrine tests to unmask contralateral upper lid pseudoretraction. PMID:8305369

  6. Vision System with Dominant Eye

    NASA Astrophysics Data System (ADS)

    Shimizu, Sota; Ishikawa, Kichiro; Suzuki, Taro; Hashizume, Takumi

    A vision system with a dominant eye, which is inspired by the function of human vision, is demonstrated as an artificial and remote vision system. This paper focuses on a remote operation in which an operator wearing a 3D head mount display (HMD) controls a stereo camera head in order to acquire visual information, which was focused upon, from a work space. A manual operation method is proposed and implemented in order to display appropriate 3D images to the operator.

  7. Association between Ocular Sensory Dominance and Refractive Error Asymmetry

    PubMed Central

    Bi, Hua; Ekure, Edgar; Su, Binbin; Wu, Haoran; Huang, Yifei; Zhang, Bin; Jiang, Jun

    2015-01-01

    Purpose To investigate the association between ocular sensory dominance and interocular refractive error difference (IRED). Methods A total of 219 subjects were recruited. The refractive errors were determined by objective refraction with a fixation target located 6 meters away. 176 subjects were myopic, with 83 being anisometropic (IRED ? 0.75 D). 43 subjects were hyperopic, with 22 being anisometropic. Sensory dominance was measured with a continuous flashing technique with the tested eye viewing a Gabor increasing in contrast and the fellow eye viewing a Mondrian noise decreasing in contrast. The log ratio of Mondrian to Gabor’s contrasts was recorded when a subject just detected the tilting direction of the Gabor during each trial. T-test was used to compare the 50 values collected from each eye, and the t-value was used as a subject’s ocular dominance index (ODI) to quantify the degree of ocular dominance. A subject with ODI ? 2 (p < 0.05) had clear dominance and the eye with larger mean ratio was the dominant one. Otherwise, a subject had an unclear dominance. Results The anisometropic subjects had stronger ocular dominance in comparison to non-anisometropic subjects (rank-sum test, p < 0.01 for both myopic and hyperopic subjects). In anisometropic subjects with clear dominance, the amplitude of the anisometropia was correlated with ODI values (R = 0.42, p < 0.01 in myopic anisometropic subjects; R = 0.62, p < 0.01 in hyperopic anisometropic subjects). Moreover, the dominant eyes were more myopic in myopic anisometropic subjects (sign-test, p < 0.05) and less hyperopic in hyperopic anisometropic subjects (sign-test, p < 0.05). Conclusion The degree of ocular sensory dominance is associated with interocular refractive error difference. PMID:26295803

  8. The role of sensory ocular dominance on through-focus visual performance in monovision presbyopia corrections.

    PubMed

    Zheleznyak, Len; Alarcon, Aixa; Dieter, Kevin C; Tadin, Duje; Yoon, Geunyoung

    2015-01-01

    Monovision presbyopia interventions exploit the binocular nature of the visual system by independently manipulating the optical properties of the two eyes. It is unclear, however, how individual variations in ocular dominance affect visual function in monovision corrections. Here, we examined the impact of sensory ocular dominance on visual performance in both traditional and modified monovision presbyopic corrections. We recently developed a binocular adaptive optics vision simulator to correct subjects' native aberrations and induce either modified monovision (1.5 D anisometropia, spherical aberration of +0.1 and -0.4 μm in distance and near eyes, respectively, over 4 mm pupils) or traditional monovision (1.5 D anisometropia). To quantify both the sign and the degree of ocular dominance, we utilized binocular rivalry to estimate stimulus contrast ratios that yield balanced dominance durations for the two eyes. Through-focus visual acuity and contrast sensitivity were measured under two conditions: (a) assigning dominant and nondominant eye to distance and near, respectively, and (b) vice versa. The results revealed that through-focus visual acuity was unaffected by ocular dominance. Contrast sensitivity, however, was significantly improved when the dominant eye coincided with superior optical quality. We hypothesize that a potential mechanism behind this observation is an interaction between ocular dominance and binocular contrast summation, and thus, assignment of the dominant eye to distance or near may be an important factor to optimize contrast threshold performance at different object distances in both modified and traditional monovision. PMID:26024464

  9. The role of sensory ocular dominance on through-focus visual performance in monovision presbyopia corrections

    PubMed Central

    Zheleznyak, Len; Alarcon, Aixa; Dieter, Kevin C.; Tadin, Duje; Yoon, Geunyoung

    2015-01-01

    Monovision presbyopia interventions exploit the binocular nature of the visual system by independently manipulating the optical properties of the two eyes. It is unclear, however, how individual variations in ocular dominance affect visual function in monovision corrections. Here, we examined the impact of sensory ocular dominance on visual performance in both traditional and modified monovision presbyopic corrections. We recently developed a binocular adaptive optics vision simulator to correct subjects' native aberrations and induce either modified monovision (1.5?D anisometropia, spherical aberration of +0.1 and ?0.4 ?m in distance and near eyes, respectively, over 4 mm pupils) or traditional monovision (1.5 D anisometropia). To quantify both the sign and the degree of ocular dominance, we utilized binocular rivalry to estimate stimulus contrast ratios that yield balanced dominance durations for the two eyes. Through-focus visual acuity and contrast sensitivity were measured under two conditions: (a) assigning dominant and nondominant eye to distance and near, respectively, and (b) vice versa. The results revealed that through-focus visual acuity was unaffected by ocular dominance. Contrast sensitivity, however, was significantly improved when the dominant eye coincided with superior optical quality. We hypothesize that a potential mechanism behind this observation is an interaction between ocular dominance and binocular contrast summation, and thus, assignment of the dominant eye to distance or near may be an important factor to optimize contrast threshold performance at different object distances in both modified and traditional monovision. PMID:26024464

  10. Eye Movement as an Indicator of Sensory Components in Thought.

    ERIC Educational Resources Information Center

    Buckner, Michael; And Others

    1987-01-01

    Investigated Neuro-Linguistic Programming eye movement model's claim that specific eye movements are indicative of specific sensory components in thought. Agreement between students' (N=48) self-reports and trained observers' records support visual and auditory portions of model; do not support kinesthetic portion. Interrater agreement supports…

  11. Real-time modulation of perceptual eye dominance in humans

    PubMed Central

    Zhou, Jiawei; Reynaud, Alexandre; Hess, Robert F.

    2014-01-01

    Ocular dominance (OD) has long served as the model for neural plasticity. The shift of OD has been demonstrated by monocular deprivation in animals only during early visual development. Here, for the first time, we show that perceptual eye dominance can be modulated in real time in normal human adults by varying the spatial image content of movies seen dichoptically by the two eyes over a period as short as 2.5 h. Unlike OD shifts seen in early visual development, this modulation in human eye dominance is not simply a consequence of reduced interocular correlation (e.g. synchronicity) or overall contrast energy, but due to the amplitude reductions of specific image components in one eye's view. The spatial properties driving this eye dominance change suggest that the underlying mechanism is binocular but not orientationally selective, therefore uniquely locating it to layer 4 B of area V1. PMID:25274364

  12. Sensory eye balance in surgically corrected intermittent exotropes with normal stereopsis

    PubMed Central

    Feng, Lixia; Zhou, Jiawei; Chen, Li; Hess, Robert F.

    2015-01-01

    Surgery to align a deviated or strabismic eye is often done for both functional as well as cosmetic reasons. Although amblyopia is often an impediment to regaining full binocularity in strabismics in general, intermittent exotropes, because their deviation is intermittent, have no amblyopia and some degree of stereopsis. Binocular function, including a balanced ocular dominance, could be expected to be normal after surgical correction if normal levels of stereopsis and visual acuity are postsurgically achieved. Here we used a binocular phase combination paradigm to quantitatively assess the ocular dominance in a group of surgically corrected intermittent exotropes who have normal stereo and visual acuity as defined clinically. Interestingly, we found significant interocular imbalance (balance point?eyes may still have a residual sensory imbalance in surgically corrected strabismus even if stereopsis is within normal limits. Our study opens the possibility that a further treatment aimed at re-balancing the ocular dominance might be necessary in surgically treated intermittent exotropia to provide more efficient binocular processing in the long term. PMID:26287935

  13. DOES DYSLEXIA DEVELOP FROM LEFT-EYE DOMINANCE?

    PubMed

    Mather, David S; Milford, Todd M; Mcrae, Lona M

    2015-10-01

    The purpose of this theoretical analysis and synthesis is to indicate how left-eye sighting dominance may lead to reading failure through dysfunctional right hemisphere letter encoding. Differing compensatory strategies are postulated to lead to outcomes that include the development of the phonologically impaired and phonologically proficient subtypes of dyslexia as well as specific spelling disability. Evidence is presented indicating that these disorders might be prevented by delaying the introduction of letter writing until the age of 8 years. Early childhood speech categorization in children genetically at-risk of developing dyslexia is also considered from this perspective. Convergent support for this premature writing hypothesis is provided by a comparison with the development of the left-hand inverted writing posture. PMID:26474440

  14. Ectopic eyes outside the head in Xenopus tadpoles provide sensory data for light-mediated learning

    PubMed Central

    Blackiston, Douglas J.; Levin, Michael

    2013-01-01

    SUMMARY A major roadblock in the biomedical treatment of human sensory disorders, including blindness, has been an incomplete understanding of the nervous system and its ability to adapt to changes in sensory modality. Likewise, fundamental insight into the evolvability of complex functional anatomies requires understanding brain plasticity and the interaction between the nervous system and body architecture. While advances have been made in the generation of artificial and biological replacement components, the brain's ability to interpret sensory information arising from ectopic locations is not well understood. We report the use of eye primordia grafts to create ectopic eyes along the body axis of Xenopus tadpoles. These eyes are morphologically identical to native eyes and can be induced at caudal locations. Cell labeling studies reveal that eyes created in the tail send projections to the stomach and trunk. To assess function we performed light-mediated learning assays using an automated machine vision and environmental control system. The results demonstrate that ectopic eyes in the tail of Xenopus tadpoles could confer vision to the host. Thus ectopic visual organs were functional even when present at posterior locations. These data and protocols demonstrate the ability of vertebrate brains to interpret sensory input from ectopic structures and incorporate them into adaptive behavioral programs. This tractable new model for understanding the robust plasticity of the central nervous system has significant implications for regenerative medicine and sensory augmentation technology. PMID:23447666

  15. ENDOGENOUS EYE BLINKS, ERP CORRELATES OF EARLY SENSORY PROCESSING AND MORNING NUTRITION

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Processes associated with spontaneously occurring eye blinks have been shown to play an active role in information processing and performance. In this report we consider whether a blink-related influence on ERPs reflecting early sensory processing could be shown and if these processes are influenced...

  16. Discovery of some 400 million year-old sensory structures in the compound eyes of trilobites.

    PubMed

    Schoenemann, Brigitte; Clarkson, Euan N K

    2013-01-01

    Fossilised arthropod compound eyes have frequently been described. Among the oldest known are those from the lower Cambrian of the Chengjiang Lagerstätte (China, c 525 Ma). All these compound eyes, though often excellently preserved, however, represent just the outer shells, because soft tissues, or even individual cells, usually do not fossilise. Using modern techniques, including ?ct-scanning and synchrotron radiation analysis we present the discovery of the sensory cell system of compound eyes, belonging to trilobites around 400 million years old, which allows their description and analysis. They are interpreted as forming part of an apposition-like ommatidium, which is a basic functional type of compound eye present in arthropods of today. Considered in greater detail, it is similar to the compound eye of the horseshoe crab Limulus, generally regarded as a 'living fossil', which probably retained this ancient basal system successfully until today. PMID:23492459

  17. Discovery of some 400 million year-old sensory structures in the compound eyes of trilobites

    PubMed Central

    Schoenemann, Brigitte; Clarkson, Euan N. K.

    2013-01-01

    Fossilised arthropod compound eyes have frequently been described. Among the oldest known are those from the lower Cambrian of the Chengjiang Lagerstätte (China, c 525 Ma). All these compound eyes, though often excellently preserved, however, represent just the outer shells, because soft tissues, or even individual cells, usually do not fossilise. Using modern techniques, including μct-scanning and synchrotron radiation analysis we present the discovery of the sensory cell system of compound eyes, belonging to trilobites around 400 million years old, which allows their description and analysis. They are interpreted as forming part of an apposition-like ommatidium, which is a basic functional type of compound eye present in arthropods of today. Considered in greater detail, it is similar to the compound eye of the horseshoe crab Limulus, generally regarded as a ‘living fossil’, which probably retained this ancient basal system successfully until today. PMID:23492459

  18. Shared Sensory Estimates for Human Motion Perception and Pursuit Eye Movements

    PubMed Central

    Mukherjee, Trishna; Battifarano, Matthew; Simoncini, Claudio

    2015-01-01

    Are sensory estimates formed centrally in the brain and then shared between perceptual and motor pathways or is centrally represented sensory activity decoded independently to drive awareness and action? Questions about the brain's information flow pose a challenge because systems-level estimates of environmental signals are only accessible indirectly as behavior. Assessing whether sensory estimates are shared between perceptual and motor circuits requires comparing perceptual reports with motor behavior arising from the same sensory activity. Extrastriate visual cortex both mediates the perception of visual motion and provides the visual inputs for behaviors such as smooth pursuit eye movements. Pursuit has been a valuable testing ground for theories of sensory information processing because the neural circuits and physiological response properties of motion-responsive cortical areas are well studied, sensory estimates of visual motion signals are formed quickly, and the initiation of pursuit is closely coupled to sensory estimates of target motion. Here, we analyzed variability in visually driven smooth pursuit and perceptual reports of target direction and speed in human subjects while we manipulated the signal-to-noise level of motion estimates. Comparable levels of variability throughout viewing time and across conditions provide evidence for shared noise sources in the perception and action pathways arising from a common sensory estimate. We found that conditions that create poor, low-gain pursuit create a discrepancy between the precision of perception and that of pursuit. Differences in pursuit gain arising from differences in optic flow strength in the stimulus reconcile much of the controversy on this topic. PMID:26041919

  19. Absence of binocular summation, eye dominance, and learning effects in color discrimination.

    PubMed

    Costa, Marcelo Fernandes; Ventura, Dora Fix; Perazzolo, Felipe; Murakoshi, Marcio; Silveira, Luiz Carlos de Lima

    2006-01-01

    We evaluated binocular summation, eye dominance, and learning in the Trivector and Ellipses procedures of the Cambridge Colour Test (CCT). Subjects (n = 36, 18-30 years old) were recruited among students and staff from the University of São Paulo. Inclusion criteria were absence of ophthalmological complaints and best-corrected Snellen VA 20/20 or better. The subjects were tested in three randomly selected eye conditions: binocular, monocular dominant eye, and nondominant eye. Results obtained in the binocular and monocular conditions did not differ statistically for thresholds measured along the protan, deutan, and tritan confusion axes (ANOVA, P > 0.05). No statistical difference was detected among discrimination ellipses obtained in binocular or monocular conditions (ANOVA, P > 0.05), suggesting absence of binocular summation or of an effect of eye dominance. Possible effects of learning were examined by comparing successive thresholds obtained in the three testing conditions. There was no evidence of improvement as a function of testing order (ANCOVA, P > 0.05). We conclude that CCT thresholds are not affected by binocularity, eye dominance, or learning. Our results differ from those found by Verriest et al. (1982) using the Farnsworth-Munsell 100 Hue test and Hovis et al. (2004) using the Farnsworth-Munsell panel D-15 test. PMID:16961981

  20. Eye-specific suppression in human LGN reflects perceptual dominance during binocular rivalry

    PubMed Central

    Haynes, John-Dylan; Deichmann, Ralf; Rees, Geraint

    2006-01-01

    When dissimilar images are presented to the two eyes, they compete for perceptual dominance so that each image is visible in turn for a few seconds while the other is suppressed. Such binocular rivalry is associated with relative suppression of local, eye-based representations1–4, that are also modulated by high-level influences such as perceptual grouping3,5. But currently it is unclear how early in visual processing the suppression of eye-based signals can occur. Here, we used high spatial resolution fMRI in conjunction with a novel binocular rivalry stimulus to show that signals recorded from the human lateral geniculate nucleus (LGN) exhibit eye-specific suppression during rivalry. Regions of LGN that showed strong eye-preference independently showed strongly reduced activity during binocular rivalry, when the stimulus presented in their preferred eye was perceptually suppressed. The human LGN is thus the earliest stage of visual processing that reflects eye-specific dominance and suppression. PMID:16244649

  1. Using an auditory sensory substitution device to augment vision: evidence from eye movements.

    PubMed

    Wright, Thomas D; Margolis, Aaron; Ward, Jamie

    2015-03-01

    Sensory substitution devices convert information normally associated with one sense into another sense (e.g. converting vision into sound). This is often done to compensate for an impaired sense. The present research uses a multimodal approach in which both natural vision and sound-from-vision ('soundscapes') are simultaneously presented. Although there is a systematic correspondence between what is seen and what is heard, we introduce a local discrepancy between the signals (the presence of a target object that is heard but not seen) that the participant is required to locate. In addition to behavioural responses, the participants' gaze is monitored with eye-tracking. Although the target object is only presented in the auditory channel, behavioural performance is enhanced when visual information relating to the non-target background is presented. In this instance, vision may be used to generate predictions about the soundscape that enhances the ability to detect the hidden auditory object. The eye-tracking data reveal that participants look for longer in the quadrant containing the auditory target even when they subsequently judge it to be located elsewhere. As such, eye movements generated by soundscapes reveal the knowledge of the target location that does not necessarily correspond to the actual judgment made. The results provide a proof of principle that multimodal sensory substitution may be of benefit to visually impaired people with some residual vision and, in normally sighted participants, for guiding search within complex scenes. PMID:25511162

  2. Monocular tool control, eye dominance, and laterality in New Caledonian crows.

    PubMed

    Martinho, Antone; Burns, Zackory T; von Bayern, Auguste M P; Kacelnik, Alex

    2014-12-15

    Tool use, though rare, is taxonomically widespread, but morphological adaptations for tool use are virtually unknown. We focus on the New Caledonian crow (NCC, Corvus moneduloides), which displays some of the most innovative tool-related behavior among nonhumans. One of their major food sources is larvae extracted from burrows with sticks held diagonally in the bill, oriented with individual, but not species-wide, laterality. Among possible behavioral and anatomical adaptations for tool use, NCCs possess unusually wide binocular visual fields (up to 60°), suggesting that extreme binocular vision may facilitate tool use. Here, we establish that during natural extractions, tool tips can only be viewed by the contralateral eye. Thus, maintaining binocular view of tool tips is unlikely to have selected for wide binocular fields; the selective factor is more likely to have been to allow each eye to see far enough across the midsagittal line to view the tool's tip monocularly. Consequently, we tested the hypothesis that tool side preference follows eye preference and found that eye dominance does predict tool laterality across individuals. This contrasts with humans' species-wide motor laterality and uncorrelated motor-visual laterality, possibly because bill-held tools are viewed monocularly and move in concert with eyes, whereas hand-held tools are visible to both eyes and allow independent combinations of eye preference and handedness. This difference may affect other models of coordination between vision and mechanical control, not necessarily involving tools. PMID:25484292

  3. Hand-Eye Dominance and Depth Perception Effects in Performance on a Basic Laparoscopic Skills Set

    PubMed Central

    Suleman, Rabiya; Yang, Tong; Paige, John; Chauvin, Sheila; Alleyn, Jaime; Brewer, Martha; Johnson, Stephen I.

    2010-01-01

    Objectives: Our study determined whether depth perception defects and hand-eye dominance affect an individual's ability to perform laparoscopic skills. Methods: The study cohort comprised 104 third-year medical students from LSU School of Medicine who completed a questionnaire including information on handedness and were tested for eye dominance and depth perception by using standardized methods. Training sessions involved an initial recorded performance, a 20-minute practice session, followed by a final recorded performance. Recorded sessions were randomized and rated by using a visual analog scale (maximal possible score = 16) based on overall performance (OPS) and depth perception (DPS). A general linear model was used to correlate depth perception defects and hand-eye dominance with assessment scores for OPS and DPS. Results: Students with depth perception defects scored significantly lower on their initial performance than did those with normal depth perception (OPS, 4.80 vs. 7.16, P=0.0008; DPS, 5.25 vs. 6.93, P=0.0195). After training, the depth perception defect group continued to have lower scores compared with the normal depth perception group. However, the 2 groups showed similar increases in pre- to posttraining performance scores (OPS, 3.84 vs. 3.18, P=0.0732). Hand-eye dominance did not significantly affect scores. Conclusions: Depth perception defects appear to compromise an individual's ability to perform basic laparoscopic skills. Individuals with defects can improve their skills by a proportion comparable to that of people with uncompromised depth perception. Differences in hand-eye dominance do not correlate with performance differences in basic laparoscopic skills. Although further research is necessary, the findings indicate that training can be tailored for individuals with depth perception defects to improve laparoscopic performance. PMID:20529525

  4. Female dominance in blue-eyed black lemurs(Eulemur macaco flavifrons).

    PubMed

    Digby, Leslie J; Kahlenberg, Sonya M

    2002-07-01

    Female dominance is unusual among mammals and has been described in detail for only a handful of species. Here we present data on the frequency and outcome of dominance interactions in seven semi-free ranging and captive groups of blue-eyed black lemurs (Eulemur macaco flavifrons) housed at the Duke University Primate Center. We collected over 260 hours of focal data during which all occurrences of dominant-subordinate interactions were recorded. We collected data outside the typical breeding and birthing seasons for this species, thus eliminating possible confounding factors and increased aggression associated with these periods. We found that females were dominant over males in all seven groups, with females winning 99% of all dominance interactions. E. m. flavifrons used aggressive dominance (e.g. chase, cuff, bite) in 81% of all interactions, with the remainder of interactions being decided using social dominance (e.g. deference in the form of supplants or cowers). Older females were dominant over younger females in two out of three multi-female groups (in each case, younger females were daughters), and younger males (sons of the dominant female) received less aggression from females than did older males (n = 2 groups). Caging and group size appear to play a minimal role in the expression of female dominance. While confirmation must await further observations on free-ranging groups of E. m. flavifrons, our data strongly suggest that this subspecies can be characterized as female dominant. PMID:12145400

  5. Effects of eye dominance (left vs. right) and cannabis use on intermanual coordination and negative symptoms in schizophrenia patients.

    PubMed

    Gorynia, Inge; Schwaiger, Markus; Heinz, Andreas

    2014-12-01

    Based on the previous findings, it has been assumed that in schizophrenia patients, eye dominance and cannabis use will affect negative symptoms and intermanual coordination (IMC), an index of interhemispheric communication. But eye dominance, specifically the clinical findings for it, has been neglected in schizophrenia research. We therefore investigated its effects in 52 right-handed (36 right-eyed and 16 left-eyed) and 51 left-handed (35 left-eyed and 16 right-eyed) schizophrenia in-patients without and with drug use. Eye dominance affected IMC in all schizophrenia patients. When comparing right- and left-handers, we found that this result was only significant in the right-handed patients and in the smaller subgroup without drug use. In the right-handers, left eye dominance-like left-handedness-was associated with higher values in IMC and less pronounced manifestation of negative symptoms, right eye dominance was not. Thus, left-eyed right-handers may be more closely related to left-handers than to right-handers. In accordance with the results from the literature, we suggest that these findings are due to better interhemispheric connections and less impairment of white matter structures, especially in right-hemispheric regions. Moreover, cannabis use was related to higher scores in IMC and less pronounced negative symptoms, but only in the right-eyed and not in the left-eyed right-handers or in the left-handers. Hence, differences in eye dominance and handedness may be partially responsible for different results in interhemispheric connections among cannabis users. In conclusion, both eye dominance and use of cannabis should be taken into account when assessing clinical symptoms in schizophrenia patients. PMID:24792218

  6. Development of a sensory neuronal cell model for the estimation of mild eye irritation.

    PubMed

    Lilja, Johanna; Forsby, Anna

    2004-10-01

    In an attempt to improve the in vitro test strategy for the estimation of eye irritation, a neuronal cell model has been developed, with cells expressing vanilloid receptor type 1 (VR1) nociceptors. The currently accepted method for measuring eye irritancy is the ethically and scientifically criticised Draize rabbit eye test, despite the fact that alternative in vitro methods are available which have proved to be reliable and reproducible for predicting severe ocular toxicity. However, no alternative tests for measuring neuronal stimulation have yet been developed, and the prediction of eye irritation in the mild range is therefore insufficient. VR1 is a nociceptor localised in C-fibre neurons innervating the cornea and the surrounding tissue, and it responds to potentially damaging stimuli by releasing Ca2+ into the cytoplasm. As a sensory endpoint, [Ca2+]i was measured in VR1 transfected cells, as well as in control cells. Short-term cell cytotoxicity studies (cell membrane rupture and morphological divergence) were used to determine the non-corrosive concentrations of the test chemicals. Preliminary results indicated that hygiene products used daily may induce eye irritation via VR1 nociceptors. The lowest toxic concentration (0.025%) of liquid hand soap, as determined by morphologic divergences of cells, generated an 80% increase in [Ca2+]i over the basal [Ca2+]i in VR1 transfected cells, whereas the non-specific [Ca2+]i increased by 33%. Furthermore, all the endpoints studied indicated that shampoo for children was less active than shampoo for adults. If this method is successfully validated with standardised reference chemicals, the model could complete the test battery of in vitro alternatives, resulting in the saving of thousands of laboratory animals. PMID:15651917

  7. Nomen est omen: Investigating the dominance of nouns in word comprehension with eye movement analyses.

    PubMed Central

    Furtner, Marco R.; Rauthmann, John F.; Sachse, Pierre

    2009-01-01

    Although nouns are easily learned in early stages of lexical development, their role in adult word and text comprehension remains unexplored thus far. To investigate the role of different word classes (open-class words: nouns, adjectives, verbs; closed-class words: pronouns, prepositions, conjunctions, etc.), 141 participants read a transposed German text while recording eye movements. Subsequently, participants indicated words they found difficult and reproduced the story. Then, participants were presented an untransposed text version while also tracking eye movements. Word difficulty, subjectively assessed by an interview and objectively by eye movement criteria (general fixation rate, number of fixations on specific words), text comprehension scores, and regressive fixations from one word class to another in the transposed text indicated that the noun was the most influential word class in enhancing the comprehension of other words. Developmental, intercultural, and neurophysiological aspects of noun dominance are discussed. PMID:20523853

  8. Biochemical Basis for Dominant Inheritance, Variable Penetrance, and Maternal Effects in RBP4 Congenital Eye Disease.

    PubMed

    Chou, Christopher M; Nelson, Christine; Tarlé, Susan A; Pribila, Jonathan T; Bardakjian, Tanya; Woods, Sean; Schneider, Adele; Glaser, Tom

    2015-04-23

    Gestational vitamin A (retinol) deficiency poses a risk for ocular birth defects and blindness. We identified missense mutations in RBP4, encoding serum retinol binding protein, in three families with eye malformations of differing severity, including bilateral anophthalmia. The mutant phenotypes exhibit dominant inheritance, but incomplete penetrance. Maternal transmission significantly increases the probability of phenotypic expression. RBP normally delivers retinol from hepatic stores to peripheral tissues, including the placenta and fetal eye. The disease mutations greatly reduce retinol binding to RBP, yet paradoxically increase the affinity of RBP for its cell surface receptor, STRA6. By occupying STRA6 nonproductively, the dominant-negative proteins disrupt vitamin A delivery from wild-type proteins within the fetus, but also, in the case of maternal transmission, at the placenta. These findings establish a previously uncharacterized mode of maternal inheritance, distinct from imprinting and oocyte-derived mRNA, and define a group of hereditary disorders plausibly modulated by dietary vitamin A. PMID:25910211

  9. Changes in Sensory Dominance during Childhood: Converging Evidence from the Colavita Effect and the Sound-Induced Flash Illusion

    ERIC Educational Resources Information Center

    Nava, Elena; Pavani, Francesco

    2013-01-01

    In human adults, visual dominance emerges in several multisensory tasks. In children, auditory dominance has been reported up to 4 years of age. To establish when sensory dominance changes during development, 41 children (6-7, 9-10, and 11-12 years) were tested on the Colavita task (Experiment 1) and 32 children (6-7, 9-10, and 11-12 years) were…

  10. Changes in Sensory Dominance during Childhood: Converging Evidence from the Colavita Effect and the Sound-Induced Flash Illusion

    ERIC Educational Resources Information Center

    Nava, Elena; Pavani, Francesco

    2013-01-01

    In human adults, visual dominance emerges in several multisensory tasks. In children, auditory dominance has been reported up to 4 years of age. To establish when sensory dominance changes during development, 41 children (6-7, 9-10, and 11-12 years) were tested on the Colavita task (Experiment 1) and 32 children (6-7, 9-10, and 11-12 years) were…

  11. Prevalence of Mutations in eyeGENE Probands With a Diagnosis of Autosomal Dominant Retinitis Pigmentosa

    PubMed Central

    Sullivan, Lori S.; Bowne, Sara J.; Reeves, Melissa J.; Blain, Delphine; Goetz, Kerry; NDifor, Vida; Vitez, Sally; Wang, Xinjing; Tumminia, Santa J.; Daiger, Stephen P.

    2013-01-01

    Purpose. To screen samples from patients with presumed autosomal dominant retinitis pigmentosa (adRP) for mutations in 12 disease genes as a contribution to the research and treatment goals of the National Ophthalmic Disease Genotyping and Phenotyping Network (eyeGENE). Methods. DNA samples were obtained from eyeGENE. A total of 170 probands with an intake diagnosis of adRP were tested through enrollment in eyeGENE. The 10 most common genes causing adRP (IMPDH1, KLHL7, NR2E3, PRPF3/RP18, PRPF31/RP11, PRPF8/RP13, PRPH2/RDS, RHO, RP1, and TOPORS) were chosen for PCR-based dideoxy sequencing, along with the two X-linked RP genes, RPGR and RP2. RHO, PRPH2, PRPF31, RPGR, and RP2 were completely sequenced, while only mutation hotspots in the other genes were analyzed. Results. Disease-causing mutations were identified in 52% of the probands. The frequencies of disease-causing mutations in the 12 genes were consistent with previous studies. Conclusions. The Laboratory for Molecular Diagnosis of Inherited Eye Disease at the University of Texas in Houston has thus far received DNA samples from 170 families with a diagnosis of adRP from the eyeGENE Network. Disease-causing mutations in autosomal genes were identified in 48% (81/170) of these families while mutations in X-linked genes accounted for an additional 4% (7/170). Of the 55 distinct mutations detected, 19 (33%) have not been previously reported. All diagnostic results were returned by eyeGENE to participating patients via their referring clinician. These genotyped samples along with their corresponding phenotypic information are also available to researchers who may request access to them for further study of these ophthalmic disorders. (ClinicalTrials.gov number, NCT00378742.) PMID:23950152

  12. Dominant defects in Drosophila eye pigmentation resulting from a euchromatin-heterochromatin fusion gene.

    PubMed Central

    Rong, Y S; Golic, K G

    1998-01-01

    We have isolated a dominant mutation, pugilistDominant (pugD), that causes variegated reductions in pteridine and ommochrome pigmentation of the Drosophila eye. The effect of pugD on pteridine pigmentation is most dramatic: the only remaining pigment consists of a thin ring of pigment around the periphery of the eye with a few scattered spots in the center. The pugD mutation disrupts a gene that encodes a Drosophila homolog of the trifunctional enzyme methylenetetrahydrofolate dehydrogenase (MTHFD; E.C.1.5.1.5, E.C.3.5. 4.9, E.C.6.3.4.3). This enzyme produces a cofactor that is utilized in purine biosynthesis. Because pteridines are derived from GTP, the pigment defect may result from an impairment in the production of purines. The mutant allele consists of a portion of the MTHFD coding region fused to approximately 1 kb of highly repetitive DNA. Transcription and translation of both parts are required for the phenotype. The repetitive DNA consists of approximately 140 nearly perfect repeats of the sequence AGAGAGA, a significant component of centric heterochromatin. The unusual nature of the protein produced by this gene may be responsible for its dominance. The repetitive DNA may also account for the variegated aspect of the phenotype. It may promote occasional association of the pugD locus with centric heterochromatin, accompanied by inactivation of pugD, in a manner similar to the proposed mode of action for brownDominant. PMID:9832531

  13. Relation of eye dominancy with color vision discrimination performance ability in normal subjects

    PubMed Central

    Koçtekin, Belk?s; Gündo?an, Nimet Ünay; Alt?nta?, Ay? Gül Koçak; Yaz?c?, Ay?e Canan

    2013-01-01

    AIM To evaluate the performance of dominant eye (DE) for color vision discrimination ability among the medical students with normal color vision. METHODS Total of 50 students studying at Ba?kent University Faculty of Medicine, including 31 males (62%) and 19 females (38%), with visual acuity of 20/20 and without congenital color vision deficiency (CCVD) evaluated by Ishihara pseudoisochromatic plate test (IPPT) were recruited for this prospective comparative study upon their voluntary participation. DE was determined by the Gündo?an Method. The color discrimination ability was examined with the Farnsworth-Munsell 100 hue (FM100) test. Test was applied by two days interval to all subjects for the three times while two eyes (TE), right eye (RE) and left eye (LE) were seeing for detecting red-green (r/g), blue-yellow (b/y) local color spectral regions error scores. The error scores were evaluated for both in DE and non-dominant (NDE). P values below 0.05 were considered to be statistically significant. RESULTS The students aged 21.18±2.52 years (mean±SD). Without sex difference the RE and the LE dominancy were found 22 (44%) and 28 (56%) respectively and FM 100 test total error scores of DE in both r/g-b/y regions were found without gender difference 24.12±14.70, 34.68±18.95, respectively. For the NDE in both, r/g-b/y regions error scores without gender difference were 32.20±19.21, 36.24±17.56, respectively. The difference of total error scores between the DE and NDE was found as 58.80±29.92, 68.44±31.46. The statistical differences among the DE and the NDE in r/g local region and total error scores were found significant in both genders (P<0.05, P<0.001). CONCLUSION The color vision discrimination performance ability was found prominent for DE. This superiority was attributed to higher sensitivity of the r/g local color spectral region. We conclude that DE has priority in r/g color spectral region, probably including inhibition of NDE. PMID:24195058

  14. Novel Dominant-Negative Mutation Within the Six Domain of the Conserved Eye Specification Gene sine oculis Inhibits Eye Development in Drosophila

    PubMed Central

    Roederer, Kristin; Cozy, Loralyn; Anderson, Jason; Kumar, Justin P.

    2009-01-01

    The development of the compound eye of Drosophila is controlled, in part, by the concerted actions of several nuclear proteins that form an intricate regulatory system. One member of this network is sine oculis (so), the founding member of the Six gene family. Mutations within so affect the entire visual system, including the compound eye. The vertebrate homologs Six3 and Six6 also appear to play crucial roles in retinal formation. Mutations in Six3 inhibit retinal formation in chickens and fish, whereas those in Six6 are the underlying cause of bilateral anophthalmia in humans. Together, these phenotypes suggest a conserved role for the Six genes in eye development. In this report, we describe the effects of a dominant-negative mutation of sine oculis on the development of the compound eye of Drosophila. The mutation resides within the Six domain and may have implications for eye development and disease. PMID:15704100

  15. Conjugate Lateral Eye Movement, Cerebral Dominance, and the Figural Creativity Factors of Fluency, Flexibility, Originality, and Elaboration.

    ERIC Educational Resources Information Center

    Doerr, Susan L.

    1980-01-01

    This study explored general relationships between figural creativity, as measured by the Torrance Tests of Creative Thinking, and cerebral dominance, as identified by the conjugate lateral eye movement (CLEM) interview procedure. Subjects were 175 adults. Results indicated no significant differences in figural creativity due to brain dominance…

  16. Binocular Neurons in Parastriate Cortex: Interocular ‘Matching’ of Receptive Field Properties, Eye Dominance and Strength of Silent Suppression

    PubMed Central

    Wang, Chun; Dreher, Bogdan

    2014-01-01

    Spike-responses of single binocular neurons were recorded from a distinct part of primary visual cortex, the parastriate cortex (cytoarchitectonic area 18) of anaesthetized and immobilized domestic cats. Functional identification of neurons was based on the ratios of phase-variant (F1) component to the mean firing rate (F0) of their spike-responses to optimized (orientation, direction, spatial and temporal frequencies and size) sine-wave-luminance-modulated drifting grating patches presented separately via each eye. In over 95% of neurons, the interocular differences in the phase-sensitivities (differences in F1/F0 spike-response ratios) were small (≤0.3) and in over 80% of neurons, the interocular differences in preferred orientations were ≤10°. The interocular correlations of the direction selectivity indices and optimal spatial frequencies, like those of the phase sensitivies and optimal orientations, were also strong (coefficients of correlation r ≥0.7005). By contrast, the interocular correlations of the optimal temporal frequencies, the diameters of summation areas of the excitatory responses and suppression indices were weak (coefficients of correlation r ≤0.4585). In cells with high eye dominance indices (HEDI cells), the mean magnitudes of suppressions evoked by stimulation of silent, extra-classical receptive fields via the non-dominant eyes, were significantly greater than those when the stimuli were presented via the dominant eyes. We argue that the well documented ‘eye-origin specific’ segregation of the lateral geniculate inputs underpinning distinct eye dominance columns in primary visual cortices of mammals with frontally positioned eyes (distinct eye dominance columns), combined with significant interocular differences in the strength of silent suppressive fields, putatively contribute to binocular stereoscopic vision. PMID:24927276

  17. Saturation mutagenesis for dominant eye morphological defects in the mouse Mus musculus.

    PubMed

    Favor, J; Neuhäuser-Klaus, A

    2000-07-01

    We have summarized our extensive series of mutagenesis experiments to isolate dominant mutations in the mouse that express eye morphological defects. Thirty-two experimental groups in which parental mice were exposed to chemical mutagens or irradiation and a historical control group of the laboratory are presented. The largest series of experiments included parental exposure to ethylnitrosourea or irradiation. A total of 203 dominant mutants were confirmed among 456,890 offspring screened, which represents one of the largest collections of mutations in the mouse affecting one organ following a systematic screen of offspring of mutagenized animals. The largest group of mutations (92) was recovered in offspring of parental mice exposed to ethylnitrosourea. The second largest group of mutations (62) was recovered in irradiation experiments. Fifty-six mutations recovered in ethylnitrosourea experiments have been mapped to 22 loci. The affected genes have been identified for a number of the recovered mutations including Cryga, Crygb, Cgyge, Pax6, Pax2, Mitf, Lim2, and Cx50. On the basis of our experiences, a number of considerations when undertaking such screens are discussed, including a) choice of mutagen, b) experimental design, and c) the criteria for such experiments to ensure that mutations at novel loci will be recovered. PMID:10886015

  18. Binocular Summation and Other Forms of Non-Dominant Eye Contribution in Individuals with Strabismic Amblyopia during Habitual Viewing

    PubMed Central

    Barrett, Brendan T.; Panesar, Gurvinder K.; Scally, Andrew J.; Pacey, Ian E.

    2013-01-01

    Background Adults with amblyopia (‘lazy eye’), long-standing strabismus (ocular misalignment) or both typically do not experience visual symptoms because the signal from weaker eye is given less weight than the signal from its fellow. Here we examine the contribution of the weaker eye of individuals with strabismus and amblyopia with both eyes open and with the deviating eye in its anomalous motor position. Methodology/Results The task consisted of a blue-on-yellow detection task along a horizontal line across the central 50 degrees of the visual field. We compare the results obtained in ten individuals with strabismic amblyopia with ten visual normals. At each field location in each participant, we examined how the sensitivity exhibited under binocular conditions compared with sensitivity from four predictions, (i) a model of binocular summation, (ii) the average of the monocular sensitivities, (iii) dominant-eye sensitivity or (iv) non-dominant-eye sensitivity. The proportion of field locations for which the binocular summation model provided the best description of binocular sensitivity was similar in normals (50.6%) and amblyopes (48.2%). Average monocular sensitivity matched binocular sensitivity in 14.1% of amblyopes’ field locations compared to 8.8% of normals’. Dominant-eye sensitivity explained sensitivity at 27.1% of field locations in amblyopes but 21.2% in normals. Non-dominant-eye sensitivity explained sensitivity at 10.6% of field locations in amblyopes but 19.4% in normals. Binocular summation provided the best description of the sensitivity profile in 6/10 amblyopes compared to 7/10 of normals. In three amblyopes, dominant-eye sensitivity most closely reflected binocular sensitivity (compared to two normals) and in the remaining amblyope, binocular sensitivity approximated to an average of the monocular sensitivities. Conclusions Our results suggest a strong positive contribution in habitual viewing from the non-dominant eye in strabismic amblyopes. This is consistent with evidence from other sources that binocular mechanisms are frequently intact in strabismic and amblyopic individuals. PMID:24205005

  19. Conjugate Lateral Eye Movement, Cerebral Dominance, and the Figural Creativity Factors of Fluency, Flexibility, Originality, and Elaboration.

    ERIC Educational Resources Information Center

    Doerr, Susan L.

    1980-01-01

    This study explored general relationships between figural creativity, as measured by the Torrance Tests of Creative Thinking, and cerebral dominance, as identified by the conjugate lateral eye movement (CLEM) interview procedure. Subjects were 175 adults. Results indicated no significant differences in figural creativity due to brain dominance…

  20. Prox 1 in eye degeneration and sensory organ compensation during development and evolution of the cavefish Astyanax.

    PubMed

    Jeffery, W; Strickler, A; Guiney, S; Heyser, D; Tomarev, S

    2000-05-01

    We have investigated expression of the homeobox gene Prox 1 during eye degeneration and sensory organ compensation in cavefish embryos. The teleost Astyanax mexicanus consists of sighted surface-dwelling forms (surface fish) and several populations of blind cave-dwelling forms (cavefish), which have evolved independently. Eye formation is initiated during cavefish development, but the lens vesicle undergoes apoptosis, and the eye subsequently arrests and degenerates. The requirement of Prox 1 for lens fiber differentiation and gamma-crystallin expression in the mouse suggests that changes in the expression of this gene could be involved in cavefish eye degeneration. Surface fish and cavefish embryos stained with a Prox 1 antibody showed Prox 1 expression in the lens, neuroretina, myotomes, heart, hindbrain, and gut, as reported in other vertebrates. We found that Prox 1 expression is not altered during cavefish lens development. Prox 1 protein was detected in the lens vesicle as soon as it formed and persisted until the time of lens degeneration in each cavefish population. The cavefish lens vesicle was also shown to express a gamma-crystallin gene, suggesting that Prox 1 is functional in cavefish lens development. In addition to the tissues described above, Prox 1 is expressed in developing taste buds and neuromasts in cavefish, which are enhanced to compensate for blindness. It is concluded that the Prox 1 gene is not involved in lens degeneration, but that expansion of the Prox 1 expression domain occurs during taste bud and neuromast development in cavefish. PMID:11180826

  1. The TRK-Fused Gene Is Mutated in Hereditary Motor and Sensory Neuropathy with Proximal Dominant Involvement

    PubMed Central

    Ishiura, Hiroyuki; Sako, Wataru; Yoshida, Mari; Kawarai, Toshitaka; Tanabe, Osamu; Goto, Jun; Takahashi, Yuji; Date, Hidetoshi; Mitsui, Jun; Ahsan, Budrul; Ichikawa, Yaeko; Iwata, Atsushi; Yoshino, Hiide; Izumi, Yuishin; Fujita, Koji; Maeda, Kouji; Goto, Satoshi; Koizumi, Hidetaka; Morigaki, Ryoma; Ikemura, Masako; Yamauchi, Naoko; Murayama, Shigeo; Nicholson, Garth A.; Ito, Hidefumi; Sobue, Gen; Nakagawa, Masanori; Kaji, Ryuji; Tsuji, Shoji

    2012-01-01

    Hereditary motor and sensory neuropathy with proximal dominant involvement (HMSN-P) is an autosomal-dominant neurodegenerative disorder characterized by widespread fasciculations, proximal-predominant muscle weakness, and atrophy followed by distal sensory involvement. To date, large families affected by HMSN-P have been reported from two different regions in Japan. Linkage and haplotype analyses of two previously reported families and two new families with the use of high-density SNP arrays further defined the minimum candidate region of 3.3 Mb in chromosomal region 3q12. Exome sequencing showed an identical c.854C>T (p.Pro285Leu) mutation in the TRK-fused gene (TFG) in the four families. Detailed haplotype analysis suggested two independent origins of the mutation. Pathological studies of an autopsied patient revealed TFG- and ubiquitin-immunopositive cytoplasmic inclusions in the spinal and cortical motor neurons. Fragmentation of the Golgi apparatus, a frequent finding in amyotrophic lateral sclerosis, was also observed in the motor neurons with inclusion bodies. Moreover, TAR DNA-binding protein 43 kDa (TDP-43)-positive cytoplasmic inclusions were also demonstrated. In cultured cells expressing mutant TFG, cytoplasmic aggregation of TDP-43 was demonstrated. These findings indicate that formation of TFG-containing cytoplasmic inclusions and concomitant mislocalization of TDP-43 underlie motor neuron degeneration in HMSN-P. Pathological overlap of proteinopathies involving TFG and TDP-43 highlights a new pathway leading to motor neuron degeneration. PMID:22883144

  2. Eye Tracking Reveals Impaired Attentional Disengagement Associated with Sensory Response Patterns in Children with Autism.

    PubMed

    Sabatos-DeVito, Maura; Schipul, Sarah E; Bulluck, John C; Belger, Aysenil; Baranek, Grace T

    2016-04-01

    This study used a gap-overlap paradigm to examine the impact of distractor salience and temporal overlap on the ability to disengage and orient attention in 50 children (4-13 years) with ASD, DD and TD, and associations between attention and sensory response patterns. Results revealed impaired disengagement and orienting accuracy in ASD. Disengagement was impaired across all groups during temporal overlap for dynamic stimuli compared to static, but only ASD showed slower disengagement from multimodal relative to unimodal dynamic stimuli. Attentional disengagement had differential associations with distinct sensory response patterns in ASD and DD. Atypical sensory processing and temporal binding appear to be intertwined with development of disengagement in ASD, but longitudinal studies are needed to unravel causal pathways. PMID:26816345

  3. Dominance of local sensory signals over inter-segmental effects in a motor system: experiments.

    PubMed

    Borgmann, Anke; Toth, Tibor I; Gruhn, Matthias; Daun-Gruhn, Silvia; Büschges, Ansgar

    2012-01-31

    Legged locomotion requires that information local to one leg, and inter-segmental signals coming from the other legs are processed appropriately to establish a coordinated walking pattern. However, very little is known about the relative importance of local and inter-segmental signals when they converge upon the central pattern generators (CPGs) of different leg joints. We investigated this question on the CPG of the middle leg coxa-trochanter (CTr)-joint of the stick insect which is responsible for lifting and lowering the leg. We used a semi-intact preparation with an intact front leg stepping on a treadmill, and simultaneously stimulated load sensors of the middle leg. We found that middle leg load signals induce bursts in the middle leg depressor motoneurons (MNs). The same local load signals could also elicit rhythmic activity in the CPG of the middle leg CTr-joint when the stimulation of middle leg load sensors coincided with front leg stepping. However, the influence of front leg stepping was generally weak such that front leg stepping alone was only rarely accompanied by switching between middle leg levator and depressor MN activity. We therefore conclude that the impact of the local sensory signals on the levator-depressor motor system is stronger than the inter-segmental influence through front leg stepping. PMID:22290138

  4. AGONISTIC SENSORY EFFECTS OF AIRBORNE CHEMICALS IN MIXTURES: ODOR, NASAL PUNGENCY, AND EYE IRRITATION

    EPA Science Inventory

    Threshold responses of odor, nasal pungency (irritation), and eye irritation were measured for single chemicals (1-propanol, 1-hexanol, ethyl acetate, heptyl acetate, 2-pentanone, 2-heptanone, toluene, ethyl benzene, and propyl benzene) and mixtures of them (two three-component m...

  5. An "eye" in the gut: the appendix as a sentinel sensory organ of the immune intelligence network.

    PubMed

    Bazar, Kimberly A; Lee, Patrick Y; Joon Yun, A

    2004-01-01

    Neural systems are the traditional model of intelligence. Their complex interconnected network of wired neurons acquires, processes, and responds to environmental cues. We propose that the immune system is a parallel system of intelligence in which the gut, including the appendix, plays a prominent role in data acquisition. The immune system is essentially a virtual unwired network of interacting cells that acquires, processes, and responds to environmental data. The data is typically acquired by antigen-presenting cells (APCs) that gather antigenic information from the environment. The APCs chemically digest large antigens and deconstruct them into smaller data packets for sampling by other cells. The gut performs the same function on a larger scale. Morsels of environmental content that enter the gut are sequentially deconstructed by physical and chemical digestion. In addition to providing nutrients, the componentized contents offer environmental data to APCs in mucosa-associated lymphoid tissues (MALT) that relay the sampled information to the immune intelligence network. In this framework, positioning of the appendix immediately after the ileocecal valve is strategic: it is ideally positioned to sample environmental data in its maximally deconstructed state after small bowel digestion. For single-celled organisms, digestion of the environment has been the primary way to sample the surroundings. Prior to the emergence of complex sensory systems such as the eye, even multi-cellular organisms may have relied heavily on digestion to acquire environmental information. While the relative value of immune intelligence has diminished since the emergence of neural intelligence, organisms still use information from both systems in integrated fashion to respond appropriately to ecologic opportunities and challenges. Appendicitis may represent a momentary maladaptation in the evolutionary transition of sensory leadership from the gut to the eye. Relationships between immune dysfunctions and cognition are explored. PMID:15325028

  6. The pugilistDominant Mutation of Drosophila melanogaster: A Simple-Sequence Repeat Disorder Reveals Localized Transport in the Eye

    PubMed Central

    Rong, Yikang S.; Golic, Mary M.; Golic, Kent G.

    2016-01-01

    The pugilist-Dominant mutation results from fusion of a portion of the gene encoding the tri-functional Methylene Tetrahydrofolate Dehydrogenase (E.C.1.5.1.5, E.C.3.5.4.9, E.C.6.3.4.3) to approximately one kb of a heterochromatic satellite repeat. Expression of this fusion gene results in an unusual ring pattern of pigmentation around the eye. We carried out experiments to determine the mechanism for this pattern. By using FLP-mediated DNA mobilization to place different pugD transgenes at pre-selected sites we found that variation in repeat length makes a strong contribution to variability of the pug phenotype. This variation is manifest primarily as differences in the thickness of the pigmented ring. We show that similar phenotypic variation can also be achieved by changing gene copy number. We found that the pugD pattern is not controlled by wingless, which is normally expressed in a similar ring pattern. Finally, we found that physical injury to a pugD eye can lead to pigment deposition in parts of the eye that would not have been pigmented in the absence of injury. Our results are consistent with a model in which a metabolite vital for pigment formation is imported from the periphery of the eye, and pugD limits the extent of its transport towards the center of the eye, thus revealing the existence of a hitherto unknown mechanism of localized transport in the eye. PMID:26999432

  7. Age-dependent gait abnormalities in mice lacking the Rnf170 gene linked to human autosomal-dominant sensory ataxia.

    PubMed

    Kim, Youngsoo; Kim, Seong Hun; Kim, Kook Hwan; Chae, Sujin; Kim, Chanki; Kim, Jeongjin; Shin, Hee-Sup; Lee, Myung-Shik; Kim, Daesoo

    2015-12-20

    Really interesting new gene (RING) finger protein 170 (RNF170) is an E3 ubiquitin ligase known to mediate ubiquitination-dependent degradation of type-I inositol 1,4,5-trisphosphate receptors (ITPR1). It has recently been demonstrated that a point mutation of RNF170 gene is linked with autosomal-dominant sensory ataxia (ADSA), which is characterized by an age-dependent increase of walking abnormalities, a rare genetic disorder reported in only two families. Although this mutant allele is known to be dominant, the functional identity thereof has not been clearly established. Here, we generated mice lacking Rnf170 (Rnf170(-/-)) to evaluate the effect of its loss of function in vivo. Remarkably, Rnf170(-/-) mice began to develop gait abnormalities in old age (12 months) in the form of asynchronous stepping between diagonal limb pairs with a fixed step sequence during locomotion, while age-matched wild-type mice showed stable gait patterns using several step sequence repertoires. As reported in ADSA patients, they also showed a reduced sensitivity for proprioception and thermal nociception. Protein blot analysis revealed that the amount of Itpr1 protein was significantly elevated in the cerebellum and spinal cord but intact in the cerebral cortex in Rnf170(-/-) mice. These results suggest that the loss of Rnf170 gene function mediates ADSA-associated phenotypes and this gives insights on the cure of patients with ADSA and other age-dependent walking abnormalities. PMID:26433933

  8. Multiple manifestations of microstimulation in the optic tectum: eye movements, pupil dilations, and sensory priming.

    PubMed

    Netser, Shai; Ohayon, Shay; Gutfreund, Yoram

    2010-07-01

    It is well established that the optic tectum (or its mammalian homologue, the superior colliculus) is involved in directing gaze toward salient stimuli. However, salient stimuli typically induce orienting responses beyond gaze shifts. The role of the optic tectum in generating responses such as pupil dilation, galvanic responses, or covert shifts is not clear. In the present work, we studied the effects of microstimulation in the optic tectum of the barn owl (Tyto alba) on pupil diameter and on eye shifts. Experiments were conducted in lightly anesthetized head-restrained barn owls. We report that low-level microstimulation in the deep layers of the optic tectum readily induced pupil dilation responses (PDRs), as well as small eye movements. Electrically evoked PDRs, similar to acoustically evoked PDRs, were long-lasting and habituated to repeated stimuli. We further show that microstimulation in the external nucleus of the inferior colliculus also induced PDRs. Finally, in experiments in which tectal microstimulations were coupled with acoustic stimuli, we show a tendency of the microstimulation to enhance pupil responses and eye shifts to previously habituated acoustic stimuli. The enhancement was dependent on the site of stimulation in the tectal spatial map; responses to sounds with spatial cues that matched the site of stimulation were more enhanced compared with sounds with spatial cues that did not match. These results suggest that the optic tectum is directly involved in autonomic orienting reflexes as well as in gaze shifts, highlighting the central role of the optic tectum in mediating the body responses to salient stimuli. PMID:20427617

  9. Through the Eye of the Cyclops: Evaluating a Multi-Sensory Intervention Programme for People with Complex Disabilities.

    ERIC Educational Resources Information Center

    Mitchell, Jillian R.; van der Gaag, Anna

    2002-01-01

    A study investigated the effectiveness with two individuals with severe mental retardation of Odyssey Now (ON), a multi-sensory program designed for use with people with mental retardation. Increases in interaction and engagement were observed during the ON sessions. Both individuals interacted more with their environment during ON sessions.…

  10. Eye closure enhances dark night perceptions

    PubMed Central

    Brodoehl, Stefan; Klingner, Carsten M.; Witte, Otto W.

    2015-01-01

    We often close our eyes when we explore objects with our fingers to reduce the dominance of the visual system over our other senses. Here we show that eye closure, even in complete darkness, results in improved somatosensory perception due to a switch from visual predominance towards a somatosensory processing mode. Using a tactile discrimination task and functional neuroimaging (fMRI) data were acquired from healthy subjects with their eyes opened and closed in two environments: under ambient light and in complete darkness. Under both conditions the perception threshold decreased when subjects closed their eyes, and their fingers became more sensitive. In complete darkness, eye closure significantly increased occipital blood-oxygen-level-dependent (BOLD) activity in the somatosensory and secondary visual processing areas. This change in brain activity was associated with enhanced coupling between the sensory thalamus and somatosensory cortex; connectivity between the visual and somatosensory areas decreased. The present study demonstrates that eye closure improves somatosensory perception not merely due to the lack of visual signals; instead, the act of closing the eyes itself alters the processing mode in the brain: with eye closure the brain switches from thalamo-cortical networks with visual dominance to a non-visually dominated processing mode. PMID:26012706

  11. A database of 629 English compound words: ratings of familiarity, lexeme meaning dominance, semantic transparency, age of acquisition, imageability, and sensory experience.

    PubMed

    Juhasz, Barbara J; Lai, Yun-Hsuan; Woodcock, Michelle L

    2015-12-01

    Since the work of Taft and Forster (1976), a growing literature has examined how English compound words are recognized and organized in the mental lexicon. Much of this research has focused on whether compound words are decomposed during recognition by manipulating the word frequencies of their lexemes. However, many variables may impact morphological processing, including relational semantic variables such as semantic transparency, as well as additional form-related and semantic variables. In the present study, ratings were collected on 629 English compound words for six variables [familiarity, age of acquisition (AoA), semantic transparency, lexeme meaning dominance (LMD), imageability, and sensory experience ratings (SER)]. All of the compound words selected for this study are contained within the English Lexicon Project (Balota et al., 2007), which made it possible to use a regression approach to examine the predictive power of these variables for lexical decision and word naming performance. Analyses indicated that familiarity, AoA, imageability, and SER were all significant predictors of both lexical decision and word naming performance when they were added separately to a model containing the length and frequency of the compounds, as well as the lexeme frequencies. In addition, rated semantic transparency also predicted lexical decision performance. The database of English compound words should be beneficial to word recognition researchers who are interested in selecting items for experiments on compound words, and it will also allow researchers to conduct further analyses using the available data combined with word recognition times included in the English Lexicon Project. PMID:25361864

  12. The Drosophila T-box transcription factor Midline functions within the Notch–Delta signaling pathway to specify sensory organ precursor cell fates and regulates cell survival within the eye imaginal disc

    PubMed Central

    Das, Sudeshna; Chen, Q. Brent; Saucier, Joseph D.; Drescher, Brandon; Zong, Yan; Morgan, Sarah; Forstall, John; Meriwether, Andrew; Toranzo, Randy; Leal, Sandra M.

    2014-01-01

    We report that the T-box transcription factor Midline (Mid), an evolutionary conserved homolog of the vertebrate Tbx20 protein, functions within the Notch–Delta signaling pathway essential for specifying the fates of sensory organ precursor cells. This complements an established history of research showing that Mid regulates the cell-fate specification of diverse cell types within the developing heart, epidermis and central nervous system. Tbx20 has been detected in diverse neuronal and epithelial cells of embryonic eye tissues in both mice and humans. However, the mechanisms by which either Mid or Tbx20 function to regulate cell-fate specification or other critical aspects of eye development including cell survival have not yet been elucidated. We have also gathered preliminary evidence suggesting that Mid may play an indirect, but vital role in selecting SOP cells within the third-instar larval eye disc by regulating the expression of the proneural gene atonal. During subsequent pupal stages, Mid specifies SOP cell fates as a member of the Notch–Delta signaling hierarchy and is essential for maintaining cell viability within by inhibiting apoptotic pathways. We present several new hypotheses that seek to understand the role of Mid in regulating developmental processes downstream of the Notch receptor that are critical for specifying unique cell fates, patterning the adult eye and maintaining cellular homeostasis during eye disc morphogenesis. PMID:23962751

  13. Signaling by Sensory Receptors

    PubMed Central

    Julius, David; Nathans, Jeremy

    2012-01-01

    Sensory systems detect small molecules, mechanical perturbations, or radiation via the activation of receptor proteins and downstream signaling cascades in specialized sensory cells. In vertebrates, the two principal categories of sensory receptors are ion channels, which mediate mechanosensation, thermosensation, and acid and salt taste; and G-protein-coupled receptors (GPCRs), which mediate vision, olfaction, and sweet, bitter, and umami tastes. GPCR-based signaling in rods and cones illustrates the fundamental principles of rapid activation and inactivation, signal amplification, and gain control. Channel-based sensory systems illustrate the integration of diverse modulatory signals at the receptor, as seen in the thermosensory/pain system, and the rapid response kinetics that are possible with direct mechanical gating of a channel. Comparisons of sensory receptor gene sequences reveal numerous examples in which gene duplication and sequence divergence have created novel sensory specificities. This is the evolutionary basis for the observed diversity in temperature- and ligand-dependent gating among thermosensory channels, spectral tuning among visual pigments, and odorant binding among olfactory receptors. The coding of complex external stimuli by a limited number of sensory receptor types has led to the evolution of modality-specific and species-specific patterns of retention or loss of sensory information, a filtering operation that selectively emphasizes features in the stimulus that enhance survival in a particular ecological niche. The many specialized anatomic structures, such as the eye and ear, that house primary sensory neurons further enhance the detection of relevant stimuli. PMID:22110046

  14. Eye Infections

    MedlinePLUS

    Your eyes can get infections from bacteria, fungi, or viruses. Eye infections can occur in different parts of the eye and can affect just one eye or both. Two common eye infections are Conjunctivitis - also known as pinkeye. Conjunctivitis is ...

  15. Black Eye

    MedlinePLUS

    ... Eye Health News Consumer Alerts What Is a Black Eye? Tweet Black eye is a phrase used to describe bruising ... dark bruising in the tissue. What Is a Black Eye? Black Eye Symptoms What Causes a Black ...

  16. Identification and immunocytochemical characterization of Piccolino, a novel Piccolo splice variant selectively expressed at sensory ribbon synapses of the eye and ear.

    PubMed

    Regus-Leidig, Hanna; Ott, Corinna; Löhner, Martina; Atorf, Jenny; Fuchs, Michaela; Sedmak, Tina; Kremers, Jan; Fejtová, Anna; Gundelfinger, Eckart D; Brandstätter, Johann H

    2013-01-01

    Piccolo is one of the largest cytomatrix proteins present at active zones of chemical synapses, where it is suggested to play a role in recruiting and integrating molecules relevant for both synaptic vesicle exo- and endocytosis. Here we examined the retina of a Piccolo-mutant mouse with a targeted deletion of exon 14 in the Pclo gene. Piccolo deficiency resulted in its profound loss at conventional chemical amacrine cell synapses but retinal ribbon synapses were structurally and functionally unaffected. This led to the identification of a shorter, ribbon-specific Piccolo variant, Piccolino, present in retinal photoreceptor cells, bipolar cells, as well as in inner hair cells of the inner ear. By RT-PCR analysis and the generation of a Piccolino-specific antibody we show that non-splicing of intron 5/6 leads to premature translation termination and generation of the C-terminally truncated protein specifically expressed at active zones of ribbon synapse containing cell types. With in situ proximity ligation assays we provide evidence that this truncation leads to the absence of interaction sites for Bassoon, Munc13, and presumably also ELKS/CAST, RIM2, and the L-type Ca(2) (+) channel which exist in the full-length Piccolo at active zones of conventional chemical synapses. The putative lack of interactions with proteins of the active zone suggests a function of Piccolino at ribbon synapses of sensory neurons different from Piccolo's function at conventional chemical synapses. PMID:23936420

  17. Sensory development.

    PubMed

    Clark-Gambelunghe, Melinda B; Clark, David A

    2015-04-01

    Sensory development is complex, with both morphologic and neural components. Development of the senses begins in early fetal life, initially with structures and then in-utero stimulation initiates perception. After birth, environmental stimulants accelerate each sensory organ to nearly complete maturity several months after birth. Vision and hearing are the best studied senses and the most crucial for learning. This article focuses on the cranial senses of vision, hearing, smell, and taste. Sensory function, embryogenesis, external and genetic effects, and common malformations that may affect development are discussed, and the corresponding sensory organs are examined and evaluated. PMID:25836703

  18. Eye Allergies

    MedlinePLUS

    ... Sun Eye Health News Consumer Alerts What Are Eye Allergies? Tweet Eye allergies, called allergic conjunctivitis , are ... that Led to a Diabetes Diagnosis Find An Eye M.D. Enter zip code here Search by ...

  19. Can explicit visual feedback of postural sway efface the effects of sensory manipulations on mediolateral balance performance?

    PubMed

    Cofré Lizama, L Eduardo; Pijnappels, Mirjam; Reeves, N Peter; Verschueren, Sabine M P; van Dieën, Jaap H

    2016-02-01

    Explicit visual feedback on postural sway is often used in balance assessment and training. However, up-weighting of visual information may mask impairments of other sensory systems. We therefore aimed to determine whether the effects of somatosensory, vestibular, and proprioceptive manipulations on mediolateral balance are reduced by explicit visual feedback on mediolateral sway of the body center of mass and by the presence of visual information. We manipulated sensory inputs of the somatosensory system by transcutaneous electric nerve stimulation on the feet soles (TENS) of the vestibular system by galvanic vestibular stimulation (GVS) and of the proprioceptive system by muscle-tendon vibration (VMS) of hip abductors. The effects of these manipulations on mediolateral sway were compared with a control condition without manipulation under three visual conditions: explicit feedback of sway of the body center of mass (FB), eyes open (EO), and eyes closed (EC). Mediolateral sway was quantified as the sum of energies in the power spectrum and as the energy at the dominant frequencies in each of the manipulation signals. Repeated-measures ANOVAs were used to test effects of each of the sensory manipulations, of visual conditions and their interaction. Overall, sensory manipulations increased body sway compared with the control conditions. Absence of normal visual information had no effect on sway, while explicit feedback reduced sway. Furthermore, interactions of visual information and sensory manipulation were found at specific dominant frequencies for GVS and VMS, with explicit feedback reducing the effects of the manipulations but not effacing these. PMID:26631143

  20. Purines and sensory nerves.

    PubMed

    Burnstock, Geoffrey

    2009-01-01

    P2X and P2Y nucleotide receptors are described on sensory neurons and their peripheral and central terminals in dorsal root, nodose, trigeminal, petrosal, retinal and enteric ganglia. Peripheral terminals are activated by ATP released from local cells by mechanical deformation, hypoxia or various local agents in the carotid body, lung, gut, bladder, inner ear, eye, nasal organ, taste buds, skin, muscle and joints mediating reflex responses and nociception. Purinergic receptors on fibres in the dorsal spinal cord and brain stem are involved in reflex control of visceral and cardiovascular activity, as well as relaying nociceptive impulses to pain centres. Purinergic mechanisms are enhanced in inflammatory conditions and may be involved in migraine, pain, diseases of the special senses, bladder and gut, and the possibility that they are also implicated in arthritis, respiratory disorders and some central nervous system disorders is discussed. Finally, the development and evolution of purinergic sensory mechanisms are considered. PMID:19655112

  1. A Point Mutation in the Ubiquitin Ligase RNF170 That Causes Autosomal Dominant Sensory Ataxia Destabilizes the Protein and Impairs Inositol 1,4,5-Trisphosphate Receptor-mediated Ca2+ Signaling.

    PubMed

    Wright, Forrest A; Lu, Justine P; Sliter, Danielle A; Dupré, Nicolas; Rouleau, Guy A; Wojcikiewicz, Richard J H

    2015-05-29

    RNF170 is an endoplasmic reticulum membrane ubiquitin ligase that contributes to the ubiquitination of activated inositol 1,4,5-trisphosphate (IP3) receptors, and also, when point mutated (arginine to cysteine at position 199), causes autosomal dominant sensory ataxia (ADSA), a disease characterized by neurodegeneration in the posterior columns of the spinal cord. Here we demonstrate that this point mutation inhibits RNF170 expression and signaling via IP3 receptors. Inhibited expression of mutant RNF170 was seen in cells expressing exogenous RNF170 constructs and in ADSA lymphoblasts, and appears to result from enhanced RNF170 autoubiquitination and proteasomal degradation. The basis for these effects was probed via additional point mutations, revealing that ionic interactions between charged residues in the transmembrane domains of RNF170 are required for protein stability. In ADSA lymphoblasts, platelet-activating factor-induced Ca(2+) mobilization was significantly impaired, whereas neither Ca(2+) store content, IP3 receptor levels, nor IP3 production were altered, indicative of a functional defect at the IP3 receptor locus, which may be the cause of neurodegeneration. CRISPR/Cas9-mediated genetic deletion of RNF170 showed that RNF170 mediates the addition of all of the ubiquitin conjugates known to become attached to activated IP3 receptors (monoubiquitin and Lys(48)- and Lys(63)-linked ubiquitin chains), and that wild-type and mutant RNF170 have apparently identical ubiquitin ligase activities toward IP3 receptors. Thus, the Ca(2+) mobilization defect seen in ADSA lymphoblasts is apparently not due to aberrant IP3 receptor ubiquitination. Rather, the defect likely reflects abnormal ubiquitination of other substrates, or adaptation to the chronic reduction in RNF170 levels. PMID:25882839

  2. A novel mutation (ASn244Lys) in the peripherin/RDS gene causing autosomal dominant retinitis pigmentosa associated with bull's eye maculopathy detected by nonradioisotopic SSCP

    SciTech Connect

    Kikawa, Emi; Nakazawa, Mitsuru; Chida, Yasushi; Shiono, Takashi; Tamai, Makota )

    1994-03-01

    Retinitis pigmentosa (RP) is characterized by night blindness, an eventual loss of visual field, a diminished response on the electroretinogram, and pigmentary retinal degeneration. These features are primarily explained by the degeneration of photoreceptors. The recent development of the molecular genetic approach has enabled the identification of genes responsible for parts of autosomal dominant RP (ADRP). Rhodopsin and peripherin/RDS genes, in particular, have been successfully shown to cosegregate with ADRP. The authors, therefore, screened 42 unrelated Japanese patients with ADRP to search for mutations in the peripherin/RDS gene. The method we employed for screening was a nonradioisotopic modification of single-strand conformation polymorphism. Among 42 unrelated patients with ADRP, the DNA from one patient (SY) showed an abnormal pattern in exon 2 on SSCP. The DNA fragments were then amplified from affected and nonaffected members of the same family as SY. The alteration in the DNA sequence that was commonly found in the affected members of the family was identified as a heterozygous transversional change of C to A at the third nucleotide in codon 244, resulting in the amino acid replacement of asparagine residue with lysine residue. None of unaffected family members or 30 normal control individuals had this alteration.

  3. Age-dependent modulation of the somatosensory network upon eye closure.

    PubMed

    Brodoehl, Stefan; Klingner, Carsten; Witte, Otto W

    2016-02-01

    Eye closure even in complete darkness can improve somatosensory perception by switching the brain to a uni-sensory processing mode. This causes an increased information flow between the thalamus and the somatosensory cortex while decreasing modulation by the visual cortex. Previous work suggests that these modulations are age-dependent and that the benefit in somatosensory performance due to eye closing diminishes with age. The cause of this age-dependency and to what extent somatosensory processing is involved remains unclear. Therefore, we intended to characterize the underlying age-dependent modifications in the interaction and connectivity of different sensory networks caused by eye closure. We performed functional MR-imaging with tactile stimulation of the right hand under the conditions of opened and closed eyes in healthy young and elderly participants. Conditional Granger causality analysis was performed to assess the somatosensory and visual networks, including the thalamus. Independent of age, eye closure improved the information transfer from the thalamus to and within the somatosensory cortex. However, beyond that, we found an age-dependent recruitment strategy. Whereas young participants were characterized by an optimized information flow within the relays of the somatosensory network, elderly participants revealed a stronger modulatory influence of the visual network upon the somatosensory cortex. Our results demonstrate that the modulation of the somatosensory and visual networks by eye closure diminishes with age and that the dominance of the visual system is more pronounced in the aging brain. PMID:26546882

  4. Sensory exotropia due to keratoconus and review of the literature

    PubMed Central

    Ciftci, Suleyman; Simsek, Ali; Dogan, Eyup; Ciftci, Leyla

    2013-01-01

    This case report describes a 17-year-old boy with sensory strabismus due to keratoconus and an ipsilateral nodular lesion of the bulbar conjunctiva. The aligned eye was the right eye and keratoconus in this eye was of late onset. Vision in the left eye was poor and keratoconus was advanced in this eye. Due to the longstanding nature of the keratoconus and its occurrence in a developmentally sensitive period, sensory exotropia had developed in the left eye. There was a nodular lesion of the bulbar conjunctiva in the ipsilateral eye. If keratoconus occurs before the age of 7 years and the prolonged visual loss is not corrected, sensory strabismus can develop, as in this patient. PMID:24204108

  5. Eye Diseases

    MedlinePLUS

    ... the back of the eye Macular degeneration - a disease that destroys sharp, central vision Diabetic eye problems ... defense is to have regular checkups, because eye diseases do not always have symptoms. Early detection and ...

  6. Sensory analysis

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Sensory evaluation can answer questions about a product that instruments cannot. The human subject is the instrument, and data can provide a wealth of information for a product developer, or results can be very variable and erroneous if all the precautions to minimize bias and external noise are no...

  7. Reading strategies in mild to moderate strabismic amblyopia: an eye movement investigation.

    PubMed

    Kanonidou, Evgenia; Proudlock, Frank A; Gottlob, Irene

    2010-07-01

    PURPOSE. To investigate oculomotor strategies in strabismic amblyopia and evaluate abnormalities during monocular and binocular reading. METHODS. Eye movements were recorded with a head-mounted infrared video eye-tracker (250 Hz, <0.01 degrees resolution) in 20 strabismic amblyopes (mean age, 44.9 +/- 10.7 years) and 20 normal control subjects (mean age, 42.8 +/- 10.9 years) while they silently read paragraphs of text. Monocular reading comparisons were made between the amblyopic eye and the nondominant eye of control subjects and the nonamblyopic eye and the dominant eye of the control subjects. Binocular reading between the amblyopic and control subjects was also compared. RESULTS. Mean reading speed, number of progressive and regressive saccades per line, saccadic amplitude (of progressive saccades), and fixation duration were estimated. Inter- and intrasubject statistical comparisons were made. Reading speed was significantly slower in amblyopes than in control subjects during monocular reading with amblyopic (13.094 characters/s vs. 22.188 characters/s; P < 0.0001) and nonamblyopic eyes (16.241 characters/s vs. 22.349 characters/s, P < 0.0001), and binocularly (15.698 characters/s vs. 23.425 characters/s, P < 0.0001). In amblyopes, reading was significantly slower with the amblyopic eye than with the nonamblyopic eye in binocular viewing (P < 0.05). These differences were associated with significantly more regressive saccades and longer fixation durations, but not with changes in saccadic amplitudes. CONCLUSIONS. In strabismic amblyopia, reading is impaired, not only during monocular viewing with the amblyopic eye, but also with the nonamblyopic eye and binocularly, even though normal visual acuity pertains to the latter two conditions. The impaired reading performance is associated with differences in both the saccadic and fixational patterns, most likely as adaptation strategies to abnormal sensory experiences such as crowding and suppression. PMID:20207968

  8. Autosomal dominant

    MedlinePLUS

    ... dominant is one of several ways that a trait or disorder can be passed down (inherited) through ... Inheriting a disease, condition, or trait depends on the type of ... chromosome). It also depends on whether the trait is dominant or ...

  9. Evidence of multisensory plasticity: Asymmetrical medial geniculate body in people with one eye

    PubMed Central

    Moro, Stefania S.; Kelly, Krista R.; McKetton, Larissa; Gallie, Brenda L.; Steeves, Jennifer K.E.

    2015-01-01

    The medial geniculate body (MGB) plays a central role in auditory processing with both efferent and afferent tracts to primary auditory cortex. People who have lost one eye early in life have enhanced sound localization, lack visual over auditory dominance and integrate auditory and visual information optimally, similar to controls, despite taking longer to localize unimodal visual stimuli. Compared to controls, people with one eye have decreased lateral geniculate nuclei (LGN) volume as expected given the 50% deafferentation of the visual system. However, LGN volume is larger than predicted contralateral to the remaining eye, indicating altered structural development likely through recruitment of deafferented LGN cells. Purpose: the current study investigated whether structural MGB changes are also present in this group given the changes they exhibit in auditory processing. Methods: MGB volumes were measured in adults who had undergone early unilateral eye enucleation and were compared to binocularly intact controls. Results: unlike controls, people with one eye had a significant asymmetry with a larger left compared to right MGB, independent of eye of enucleation. MGB volume correlated positively with LGN volume in people with one eye. Conclusions: volume asymmetry in the MGB in people with one eye may represent increased interactions between the left MGB and primary auditory cortex. This interaction could contribute to increased auditory and other left hemisphere-dominant processing, including language, as compensation for the loss of one half of visual inputs early in life. The positive correlation between MGB and LGN volume is not due to space constraints but rather indicates increased plasticity in both auditory and visual sensory systems following early eye enucleation. PMID:26594632

  10. Healthy Eyes

    MedlinePLUS

    ... please turn Javascript on. Healthy Eyes Maintaining Your Vision Click for more information Taking good care of ... are qualified to perform eye exams. Aging and Vision Changes As you age, it is normal to ...

  11. Eye Emergencies

    MedlinePLUS

    ... various shapes (floaters) in the eye Blurred vision Shadow or blindness in a part of the visual ... with you to the hospital. Click below to download: The Eyes in Marfan syndrome CALL OUR HELP ...

  12. Your Eyes

    MedlinePLUS

    ... the eye and keeps it healthy. previous continue Light, Lens, Action These next parts are really cool, ... the eye. previous continue Rods and Cones Process Light The retina uses special cells called rods and ...

  13. Eye emergencies

    MedlinePLUS

    ... be caused by common household products, such as cleaning solutions, garden chemicals, solvents, or other types of ... remove it. If the object is on the surface of the eye, try gently rinsing the eye ...

  14. Your Eyes

    MedlinePLUS

    ... protection when playing racquetball, hockey, skiing, or other sports that could injure your eyes. Wear sunglasses. Too much light can damage your eyes and cause vision problems later in life. For instance, a lens ...

  15. Eye Cancer

    MedlinePLUS

    ... adults are melanoma and lymphoma. The most common eye cancer in children is retinoblastoma, which starts in the cells of the retina. ... from other parts of the body. Treatment for eye cancer varies by the type and by how advanced ...

  16. Eye Cancer

    MedlinePLUS

    ... of that menu as a roadmap to this full guide. Eye cancer is a general term used to describe many types of tumors that can start in various parts of the eye. It occurs when healthy cells in or around the eye change and grow ...

  17. The injured eye

    PubMed Central

    Scott, Robert

    2011-01-01

    Eye injuries come at a high cost to society and are avoidable. Ocular blast injuries can be primary, from the blast wave itself; secondary, from fragments carried by the blast wind; tertiary; due to structural collapse or being thrown against a fixed object; or quaternary, from burns and indirect injuries. Ballistic eye protection significantly reduces the incidence of eye injuries and should be encouraged from an early stage in Military training. Management of an injured eye requires meticulous history taking, evaluation of vision that measures the acuity and if there is a relative pupillary defect as well as careful inspection of the eyes, under anaesthetic if necessary. A lateral canthotomy with cantholysis should be performed immediately if there is a sight-threatening retrobulbar haemorrhage. Systemic antibiotics should be prescribed if there is a suspected penetrating or perforating injury. A ruptured globe should be protected by an eye shield. Primary repair of ruptured globes should be performed in a timely fashion. Secondary procedures will often be required at a later date to achieve sight preservation. A poor initial visual acuity is not a guarantee of a poor final result. The final result can be predicted after approximately 3–4 weeks. Future research in eye injuries attempts to reduce scarring and neuronal damage as well as to promote photoreceptor rescue, using post-transcriptional inhibition of cell death pathways and vaccination to promote neural recovery. Where the sight has been lost sensory substitution of a picture from a spectacle mounted video camera to the touch receptors of the tongue can be used to achieve appreciation of the outside world. PMID:21149360

  18. The injured eye.

    PubMed

    Scott, Robert

    2011-01-27

    Eye injuries come at a high cost to society and are avoidable. Ocular blast injuries can be primary, from the blast wave itself; secondary, from fragments carried by the blast wind; tertiary; due to structural collapse or being thrown against a fixed object; or quaternary, from burns and indirect injuries. Ballistic eye protection significantly reduces the incidence of eye injuries and should be encouraged from an early stage in Military training. Management of an injured eye requires meticulous history taking, evaluation of vision that measures the acuity and if there is a relative pupillary defect as well as careful inspection of the eyes, under anaesthetic if necessary. A lateral canthotomy with cantholysis should be performed immediately if there is a sight-threatening retrobulbar haemorrhage. Systemic antibiotics should be prescribed if there is a suspected penetrating or perforating injury. A ruptured globe should be protected by an eye shield. Primary repair of ruptured globes should be performed in a timely fashion. Secondary procedures will often be required at a later date to achieve sight preservation. A poor initial visual acuity is not a guarantee of a poor final result. The final result can be predicted after approximately 3-4 weeks. Future research in eye injuries attempts to reduce scarring and neuronal damage as well as to promote photoreceptor rescue, using post-transcriptional inhibition of cell death pathways and vaccination to promote neural recovery. Where the sight has been lost sensory substitution of a picture from a spectacle mounted video camera to the touch receptors of the tongue can be used to achieve appreciation of the outside world. PMID:21149360

  19. Eyes for Learning

    ERIC Educational Resources Information Center

    Orfield, Antonia

    2008-01-01

    Vision is the dominant sense, and the eyes are connected with almost every other part of the brain. If the vision system is poorly developed, children trying to learn suffer. Without good up close vision, students are handicapped even if no one knows or suspects it--they may not even know it themselves. Students do not know that the way they see…

  20. Eye Protection

    PubMed Central

    Pashby, Tom

    1986-01-01

    Eye injuries frequently occur in the home, at work and at play. Many result in legally blind eyes, and most are preventable. Awareness of potential hazards is essential to preventing eye injuries, particularly in children. In addition, protective devices must be used appropriately. We have developed eye protectors that have proved effective in reducing both the overall incidence and the severity of sports eye injuries. ImagesFigures 2a, bFigure 3Figures 4a, b, c, dFigure 5 PMID:21267100

  1. Teaching through Sensory-Motor Experiences.

    ERIC Educational Resources Information Center

    Arena, John I., Ed.

    Included in the collection are articles on sensory-motor sequencing experiences in learning by R.G. Heckelman, integrating form perception by Floria Coon-Teters, building patterns of retention by Harold Helms, hand-eye coordination by Shirley Linn, laterality and directionality by Sheila Benyon, body image and body awareness by Grace Petitclerc,…

  2. EYE DEVELOPMENT

    PubMed Central

    Baker, Nicholas E.; Li, Ke; Quiquand, Manon; Ruggiero, Robert; Wang, Lan-Hsin

    2014-01-01

    The eye has been one of the most intensively studied organs in Drosophila. The wealth of knowledge about its development, as well as the reagents that have been developed, and the fact that the eye is dispensable for survival, also make the eye suitable for genetic interaction studies and genetic screens. This chapter provides a brief overview of the methods developed to image and probe eye development at multiple developmental stages, including live imaging, immunostaining of fixed tissues, in situ hybridizations, and scanning electron microscopy and color photography of adult eyes. Also summarized are genetic approaches that can be performed in the eye, including mosaic analysis and conditional mutation, gene misexpression and knockdown, and forward genetic and modifier screens. PMID:24784530

  3. Eye Allergies

    MedlinePLUS

    ... Uveitis Focus On Pediatric Ophthalmology Education Center Oculofacial Plastic Surgery Center Laser Surgery Education Center Redmond Ethics Center Global Ophthalmology Guide Academy Publications EyeNet Ophthalmology ...

  4. Black Eye

    MedlinePLUS

    ... Uveitis Focus On Pediatric Ophthalmology Education Center Oculofacial Plastic Surgery Center Laser Surgery Education Center Redmond Ethics Center Global Ophthalmology Guide Academy Publications EyeNet Ophthalmology ...

  5. Autosomal dominant optic atrophy with asymptomatic peripheral neuropathy.

    PubMed Central

    Chalmers, R M; Bird, A C; Harding, A E

    1996-01-01

    The association between hereditary motor and sensory neuropathy (HMSN) and optic atrophy has been termed HMSN type VI. The autosomal dominant inheritance of this syndrome is reported. Three generations were affected with optic atrophy, which differed in some respects from classic dominant optic atrophy, and an asymptomatic, mainly sensory, neuropathy. PMID:8708653

  6. Eye Infections

    MedlinePLUS

    ... Listen Español Text Size Email Print Share Eye Infections in Infants & Children Page Content ​​​If the white ... be treated early to prevent serious complications. Eye infections that occur after the newborn period: These infections ...

  7. Watery eyes

    MedlinePLUS

    ... vision You have a severe injury to the eye Also, contact your health care provider if you have: A ... often does it happen? Does it affect both eyes? Do you have vision problems? Do you wear contacts or glasses? Does the tearing happen after an ...

  8. Flexibility and Stability in Sensory Processing Revealed Using Visual-to-Auditory Sensory Substitution

    PubMed Central

    Hertz, Uri; Amedi, Amir

    2015-01-01

    The classical view of sensory processing involves independent processing in sensory cortices and multisensory integration in associative areas. This hierarchical structure has been challenged by evidence of multisensory responses in sensory areas, and dynamic weighting of sensory inputs in associative areas, thus far reported independently. Here, we used a visual-to-auditory sensory substitution algorithm (SSA) to manipulate the information conveyed by sensory inputs while keeping the stimuli intact. During scan sessions before and after SSA learning, subjects were presented with visual images and auditory soundscapes. The findings reveal 2 dynamic processes. First, crossmodal attenuation of sensory cortices changed direction after SSA learning from visual attenuations of the auditory cortex to auditory attenuations of the visual cortex. Secondly, associative areas changed their sensory response profile from strongest response for visual to that for auditory. The interaction between these phenomena may play an important role in multisensory processing. Consistent features were also found in the sensory dominance in sensory areas and audiovisual convergence in associative area Middle Temporal Gyrus. These 2 factors allow for both stability and a fast, dynamic tuning of the system when required. PMID:24518756

  9. Dry Eye

    MedlinePLUS

    ... dry eye. Infrequent blinking, associated with staring at computer or video screens, may also lead to dry ... questions and comments to the NEI Office of Science Communications, Public Liaison, and Education. Technical questions about ...

  10. Dry eyes

    MedlinePLUS

    Try artificial tears, available as either drops or ointment. Ointments last longer, but are thicker and can cause blurry ... make your dry eyes better? Have you tried artificial tears? Do they help? Are you taking any ...

  11. Eye Injuries

    MedlinePLUS

    ... that you could lose your vision. Most eye injuries are preventable. If you play sports or work in certain jobs, you may need protection. The most common type of injury happens when something irritates the outer surface of ...

  12. Sensory preconditioning in honeybees.

    PubMed

    Müller, D; Gerber, B; Hellstern, F; Hammer, M; Menzel, R

    2000-04-01

    Sensory preconditioning means that reinforcement of stimulus A after unreinforced exposure to a compound AB also leads to responses to stimulus B. Here, we describe and analyze sensory preconditioning in an insect, the honeybee Apis mellifera. Using two-element odorant compounds in classical conditioning of the proboscis extension reflex, we found (i) that sensory preconditioning is not due to stimulus generalization, (ii) that paired, but not unpaired, presentation of elements supports sensory preconditioning, (iii) that simultaneous, but not sequential, exposure to the elements of the compound supports sensory preconditioning and (iv) that a single presentation of the compound yields maximal sensory preconditioning. The results are discussed with respect to configural and chain-like associative explanations for sensory preconditioning. We suggest an experience-dependent step of compound processing, establishing configural units, as an additional explanation for sensory preconditioning. PMID:10729283

  13. Novel automatic eye detection and tracking algorithm

    NASA Astrophysics Data System (ADS)

    Ghazali, Kamarul Hawari; Jadin, Mohd Shawal; Jie, Ma; Xiao, Rui

    2015-04-01

    The eye is not only one of the most complex but also the most important sensory organ of the human body. Eye detection and eye tracking are basement and hot issue in image processing. A non-invasive eye location and eye tracking is promising for hands-off gaze-based human-computer interface, fatigue detection, instrument control by paraplegic patients and so on. For this purpose, an innovation work frame is proposed to detect and tracking eye in video sequence in this paper. The contributions of this work can be divided into two parts. The first contribution is that eye filters were trained which can detect eye location efficiently and accurately without constraints on the background and skin colour. The second contribution is that a framework of tracker based on sparse representation and LK optic tracker were built which can track eye without constraint on eye status. The experimental results demonstrate the accuracy aspects and the real-time applicability of the proposed approach.

  14. Eye tracker.

    PubMed

    Pruehsner, W; Enderle, J D

    1999-01-01

    A device that records saccadic eye movements, the Eye Tracker, is presented in this paper. The Eye Tracker utilizes infra-red technology mounted on fully adjustable goggles to follow eye movements targeted by either a goggles mounted HUD type display or a wall mounted light bank. Output from the goggles is remotely sent to a PC type computer, which leads to device portability. The goggles can also maintain output data in an internal memory for latter download. The user interface is Windows based with the output from the goggles represented as a trace map or plotted points. This output can also be saved or printed for future reference. The user interface can be used on any PC type computer. The device is designed with reference to standard ISO design methodology. Safety in design and final product usage has also been addressed with reference to standard ISO type procedures. Device accuracy is maintained by precise construction of the IR units in the goggles and tight control of cross talk between each IR device plus filtering of ambient light signals. Also, a reset feature is included to maintain equal baseline control. An automatic switching device is included in the goggles to allow the Eye Tracker to "warm up," assuring that equal IR power is delivered for each subject tested. The IR units in the goggles are also modular in case replacement is required. PMID:11143354

  15. Dominantly inherited peripheral neuropathies.

    PubMed

    Vallat, Jean-Michel

    2003-07-01

    Since 1886, the year that Charcot and Marie and Tooth described a genetic "peroneal muscular atrophy syndrome," electrophysiological and histological studies of the peripheral nervous system have greatly aided the characterization of this syndrome, which falls among the hereditary sensory-motor neuropathies. Two principal forms of Charcot-Marie-Tooth (CMT) disease have been distinguished: CMT 1, corresponding to a demyelinating type, and CMT 2, corresponding to an axonal type. The modes of transmission of these types are variable, recessive or dominant, autosomal, or X-linked. Our discussion here is confined to the dominant forms. In recent years, advances in molecular biology have greatly modified the approach to CMT disease and related neuropathies (such as hereditary neuropathy with liability to pressure palsies). With increased knowledge of responsible gene mutations and several other loci identified by linkage studies, our understanding of the pathophysiology of these neuropathies is increasing; however, with greater understanding, the classification of these disorders is becoming more complex. In this review we present and discuss the currently characterized subtypes, with emphasis on their known histological aspects. While nerve biopsy has lost its diagnostic importance in certain forms of the disease, such as CMT 1A, CMT 1B, and X-linked CMT (CMT X), it remains important for better characterizing the lesions of CMT 2 and forms of genetic peroneal atrophy in which DNA study is unrevealing. PMID:12901697

  16. Eye and orbit ultrasound

    MedlinePLUS

    Echography - eye orbit; Ultrasound - eye orbit; Ocular ultrasonography; Orbital ultrasonography ... eye is numbed with medicine (anesthetic drops). The ultrasound wand (transducer) is placed against the front surface ...

  17. Healthy Eyes

    MedlinePLUS

    ... Your Doctor Financial Aid for Eye Care En español La enfermedad diabética del ojo La enfermedad diabética ... Z Site Map Information in Spanish (Información en español) Website, Social Media Policies and Other Important Links ...

  18. Eye Problems

    MedlinePLUS

    ... Begin Here 1. Is your eye tearing? Yes Go to Question 11.** No 2. Do you have blurred vision? Go to Question 8.* No 3. Have you recently ... relievers. If the bump grows or doesn't go away, see your doctor. If the redness spreads ...

  19. Googly Eyes

    ERIC Educational Resources Information Center

    Boss, Susan

    2009-01-01

    Beverage take-out trays are funky in their form and function. In this article, the author describes how to make googly eye masks out of discarded take-out trays and other common recycled or discarded materials. (Contains 1 online resource.)

  20. Electrotactile and vibrotactile displays for sensory substitution systems

    NASA Technical Reports Server (NTRS)

    Kaczmarek, Kurt A.; Webster, John G.; Bach-Y-rita, Paul; Tompkins, Willis J.

    1991-01-01

    Sensory substitution systems provide their users with environmental information through a human sensory channel (eye, ear, or skin) different from that normally used or with the information processed in some useful way. The authors review the methods used to present visual, auditory, and modified tactile information to the skin and discuss present and potential future applications of sensory substitution, including tactile vision substitution (TVS), tactile auditory substitution, and remote tactile sensing or feedback (teletouch). The relevant sensory physiology of the skin, including the mechanisms of normal touch and the mechanisms and sensations associated with electrical stimulation of the skin using surface electrodes (electrotactile, or electrocutaneous, stimulation), is reviewed. The information-processing ability of the tactile sense and its relevance to sensory substitution is briefly summarized. The limitations of current tactile display technologies are discussed.

  1. Eyes, Bulging (Proptosis)

    MedlinePLUS

    ... Unequal Vision, Blurred Vision, Double Changes in the Appearance of the Eyes Vision Loss, Sudden Other Eye ... prominent eyes. Some disorders that may change the appearance of the face and eyes but that do ...

  2. Dilating Eye Drops

    MedlinePLUS

    ... Conditions Most Common Searches Adult Strabismus Amblyopia Cataract Conjunctivitis Corneal Abrasions Dilating Eye Drops Lazy eye (defined) ... Loading... Most Common Searches Adult Strabismus Amblyopia Cataract Conjunctivitis Corneal Abrasions Dilating Eye Drops Lazy eye (defined) ...

  3. Eye muscle repair

    MedlinePLUS

    ... eye; Resection and recession; Strabismus repair; Extraocular muscle surgery ... The goal of this surgery is to restore the eye muscles to a proper position. This will help the eyes move correctly. Eye muscle surgery ...

  4. What Is Dry Eye?

    MedlinePLUS Videos and Cool Tools

    ... Management Member Services Advocacy Foundation Subspecialties & More Eye Health Home Annual Meeting Clinical Education Practice Management Member ... Center Redmond Ethics Center Global Ophthalmology Guide Eye Health Find an Eye M.D. Academy Store Eye ...

  5. Preventing Eye Injuries

    MedlinePLUS

    ... the Sun Eye Health News Consumer Alerts Preventing Eye Injuries Tweet Protecting your eyes from injury is ... as possible, even if the injury seems minor. Eye Injury Facts and Myths Men are more likely ...

  6. Eye muscle repair - discharge

    MedlinePLUS

    ... Lazy eye repair - discharge; Strabismus repair - discharge; Extraocular muscle surgery - discharge ... You or your child had eye muscle repair surgery to correct eye muscle ... term for crossed eyes is strabismus. Children most often ...

  7. LASIK - Laser Eye Surgery

    MedlinePLUS Videos and Cool Tools

    ... Management Member Services Advocacy Foundation Subspecialties & More Eye Health Home Annual Meeting Clinical Education Practice Management Member ... Center Redmond Ethics Center Global Ophthalmology Guide Eye Health Find an Eye M.D. Academy Store Eye ...

  8. Why Do Eyes Water?

    MedlinePLUS

    ... Skating Crushes What's a Booger? Why Do Eyes Water? KidsHealth > For Kids > Why Do Eyes Water? Print ... out of your nose. continue Why Do Eyes Water? Eyes water for lots of different reasons besides ...

  9. Eye Movement Disorders

    MedlinePLUS

    ... t work properly. There are many kinds of eye movement disorders. Two common ones are Strabismus - a disorder ... of the eyes, sometimes called "dancing eyes" Some eye movement disorders are present at birth. Others develop over ...

  10. Eye contricks

    PubMed Central

    Wade, Nicholas J

    2011-01-01

    Pictorial images are icons as well as eye-cons: they provide distillations of objects or ideas into simpler shapes. They create the impression of representing that which cannot be presented. Even at the level of the photograph, the links between icon and object are tenuous. The dimensions of depth and motion are missing from icons, and these alone introduce all manner of potential ambiguities. The history of art can be considered as exploring the missing link between icon and object. Eye-cons can also be illusions—tricks of vision so that what is seen does not necessarily correspond to what is physically presented. Pictorial images can be spatialised or stylised; spatialised images generally share some of the projective characteristics of the object represented. Written words are also icons, but they do not resemble the objects they represent—they are stylised or conventional. Icons as stylised words and spatialised images were set in delightful opposition by René Magritte in a series of pipe paintings, and this theme is here alluded to. Most of visual science is now concerned with icons—two-dimensional displays on computer monitors. Is vision now the science of eye-cons? PMID:23145240

  11. The effect of cataract surgery on ocular dominance

    PubMed Central

    Schwartz, Roy; Yatziv, Yossi

    2015-01-01

    Purpose The aim of this study is to assess whether eye dominance may change after cataract surgery. Methods This is a prospective case series. Cataract surgery candidates were examined prior to surgery for best-corrected visual acuity, eye dominance, and handedness. Patients with ocular conditions that may affect visual acuity were excluded from the study. A month following surgery, best-corrected visual acuity and eye dominance examinations were repeated. Results The study included 33 patients with a mean age of 70.5±9.4 years. Eighteen patients (54.5%) had right eye dominance. Following surgery, seven patients (21.2%) had a change in eye dominance. The change in dominance was linked to improved visual acuity in the operated eye and to a younger age, although with no statistical significance. Conclusion This is the first study reported in the literature to show that ocular dominance is a plastic characteristic following cataract surgeries. The results may change the importance given to eye dominance measurement prior to surgeries that rely on this examination, such as monovision surgeries. PMID:26715837

  12. Sensory Conversion Devices

    NASA Astrophysics Data System (ADS)

    Medelius, Pedro

    The human body has five basic sensory functions: touch, vision, hearing, taste, and smell. The effectiveness of one or more of these human sensory functions can be impaired as a result of trauma, congenital defects, or the normal ageing process. Converting one type of function into another, or translating a function to a different part of the body, could result in a better quality of life for a person with diminished sensorial capabilities.

  13. Sensory Correlations in Autism

    ERIC Educational Resources Information Center

    Kern, Janet K.; Trivedi, Madhukar H.; Grannemann, Bruce D.; Garver, Carolyn R.; Johnson, Danny G.; Andrews, Alonzo A.; Savla, Jayshree S.; Mehta, Jyutika A.; Schroeder, Jennifer L.

    2007-01-01

    This study examined the relationship between auditory, visual, touch, and oral sensory dysfunction in autism and their relationship to multisensory dysfunction and severity of autism. The Sensory Profile was completed on 104 persons with a diagnosis of autism, 3 to 56 years of age. Analysis showed a significant correlation between the different…

  14. [Sensory Systems of Infants.

    ERIC Educational Resources Information Center

    Zero To Three, 1993

    1993-01-01

    This newsletter contains six articles: (1) "Early Flavor Experiences: When Do They Start?" Julie A. Mennella and Gary K. Beauchamp); (2) "Infant Massage" (Tiffany Field); (3) "The Infant's Sixth Sense: Awareness and Regulation of Bodily Processes" (Stephen W. Porges); (4) "Sensory Contributions to Action: A Sensory Integrative Approach" (Marie E.…

  15. NEUROPHYSIOLOGICAL EVALUATION OF SENSORY SYSTEMS'

    EPA Science Inventory

    Exposure to many neurotoxic compounds has been shown to produce a sensory system dysfunction. Neurophysiological assessment of sensory function in humans and animal models often uses techniques known as sensory evoked potentials. Because both humans and animals show analogous res...

  16. Comments on the eyes of tardigrades.

    PubMed

    Greven, Hartmut

    2007-12-01

    A survey is given on the scarce information on the visual organs (eyes or ocelli) of Tardigrada. Many Eutardigrada and some Arthrotardigrada, namely the Echiniscidae, possess inverse pigment-cup ocelli, which are located in the outer lobe of the brain, and probably are of cerebral origin. Occurrence of such organs in tardigrades, suggested as being eyeless, has never been checked. Depending on the species, response to light (photokinesis) is negative, positive or indifferent, and may change during the ontogeny. The tardigrade eyes of the two eutardigrades examined up to now comprise a single pigment cup cell, one or two microvillous (rhabdomeric) sensory cells and ciliary sensory cell(s). In the eyes of the eutardigrade Milnesium tardigradum the cilia are differentiated in an outer branching segment and an inner (dendritic) segment. Because of the scarcity of information on the tardigrade eyes, their homology with the visual organs of other bilaterians is currently difficult to establish and further comparative studies are needed. Thus, the significance of these eyes for the evolution of arthropod visual systems is unclear yet. PMID:18089118

  17. A Parietal-Temporal Sensory-Motor Integration Area for the Human Vocal Tract: Evidence from an fMRI Study of Skilled Musicians

    ERIC Educational Resources Information Center

    Pa, Judy; Hickok, Gregory

    2008-01-01

    Several sensory-motor integration regions have been identified in parietal cortex, which appear to be organized around motor-effectors (e.g., eyes, hands). We investigated whether a sensory-motor integration area might exist for the human vocal tract. Speech requires extensive sensory-motor integration, as does other abilities such as vocal…

  18. Autosomal dominant simple microphthalmos.

    PubMed Central

    Vingolo, E M; Steindl, K; Forte, R; Zompatori, L; Iannaccone, A; Sciarra, A; Del Porto, G; Pannarale, M R

    1994-01-01

    Congenital bilateral microphthalmos is a rare malformation of the eye, which ranges from extreme to mild reduction of total axial length. Microphthalmos may occur as an isolated ocular abnormality or as part of a systemic disorder, and different classifications of the condition have been attempted. We describe a large pedigree with 14 persons in four generations affected with bilateral microphthalmos without other ocular or systemic signs. An autosomal dominant trait with complete penetrance is proposed. Five subjects underwent a complete ophthalmological evaluation. The total axial length was measured by A scan ultrasonography in all persons. Ultrasonography showed a reduction of the total axial length (range 18.4-19.7 mm) and a reduced vitreous cavity length (range 11.4-13.5 mm) in all investigated patients. All the patients had microcornea (range 8-9.7 mm). No other ocular anomalies or associated systemic malformations were found. A review of published reports also suggests that simple, partial, posterior, pure microphthalmos and nanophthalmos are similar clinical entities sharing total axial length and vitreous cavity length reduction. Therefore, the term simple microphthalmos is proposed to identify these clinical conditions. Images PMID:7815444

  19. Diabetes eye exams

    MedlinePLUS

    ... catch problems early if you get regular eye exams. ... diabetes checks your eyes, you need an eye exam every 1 to 2 years by an eye ... problems with your vision. Many can do screening exams for damage from diabetes. Once you have eye ...

  20. Eye Injuries (For Parents)

    MedlinePLUS

    ... However, do not delay flushing the eye first. Black Eyes and Blunt Injuries A black eye is often a minor injury. But this ... if you're not sure what caused the black eye. For a black eye: Apply cold compresses ...

  1. Eye Injuries (For Parents)

    MedlinePLUS

    ... Has: been struck in the eye with a ball or other object a red or irritated eye eye discomfort a swollen, red, or painful area around the eye or eyelid an eye that's very sensitive to light Seek Emergency Care Immediately If Your Child Has: ...

  2. Human sensory subsystems emulator.

    PubMed

    Frenger, P

    2001-01-01

    Last year this author presented his design for a computerized human nervous system function emulator for use in an android robot. This paper describes that emulator's sensory subsystems in more detail and adds new functions. Topics covered include sensor types, signal conditioning, data handling in the afferent pathways and interpretation of sensory information. Physiological sensory modalities (including: temperature, pressure, acceleration, humidity, sound and light stimuli) as well as nonphysiological (including: magnetic, radio, infrared, ultrasound and satellite GPS) are elucidated. The relationship of a primitive stimulus (i.e.: heat) to a high level sensation (i.e.: pain) is explored. PMID:11347421

  3. Fluorescent eye test (image)

    MedlinePLUS

    The fluorescent eye test is useful in determining if there is a scratch or other problem with the surface ... has thoroughly covered the eye a cobalt blue light is then directed on the eye. The light ...

  4. Facts About Pink Eye

    MedlinePLUS

    ... unless the person’s history suggests bacterial conjunctivitis. Viral Conjunctivitis Pink eye, also known as conjunctivitis, can cause ... of the discharge from an infected eye. Bacterial Conjunctivitis Bacterial conjunctivitis tends to occur in one eye ...

  5. Amblyopia: Lazy Eye Treatment

    MedlinePLUS

    ... to 60 Adults Over 60 Babies, Children & Teenagers Computer Usage Diabetes Diet & Nutrition Eye Injuries Eye Screening ... treatment may not be successful. Amblyopia caused by cloudiness of the eye tissue needs to be found ...

  6. What Is Dry Eye?

    MedlinePLUS Videos and Cool Tools

    ... Management Member Services Advocacy Foundation Subspecialties & More Eye Health Home Annual Meeting Clinical Education Practice Management Member ... Center Redmond Ethics Center Global Ophthalmology Guide Eye Health Find an Ophthalmologist Academy Store Eye Health A- ...

  7. Crossed eyes (image)

    MedlinePLUS

    People are very sensitive to other individuals' eye positions. By looking at another person's eye position, one can very effectively gauge where they are looking. People are also sensitive to eyes ...

  8. Using Eye Makeup

    MedlinePLUS

    ... Guidelines Home Remedies for Simple Eye Problems Medical Marijuana for Glaucoma Pregnancy Preventing Eye Injuries Smokers Sports ... away from the eye, to avoid blocking the oil glands of the upper or lower eyelid. These ...

  9. Eye Injuries at Work

    MedlinePLUS

    ... visit the emergency room each year due to workplace eye injury . Out of all eye injuries sustained on the ... In fact, in 2012 more than 20,000 workplace eye injuries required time off from work (PDF 200 KB). ...

  10. Conjunctivitis (Pink Eye)

    MedlinePLUS

    ... publications and references used throughout site. Conjunctivitis (Pink Eye) One Page Overview Pink, itchy eyes? Conjunctivitis – or ... Crusting of eyelids or lashes sometimes occurs Pink Eye: What To Do Discusses causes and treatment, suggestions ...

  11. Examining Sensory Quadrants in Autism

    ERIC Educational Resources Information Center

    Kern, Janet K.; Garver, Carolyn R.; Carmody, Thomas; Andrews, Alonzo A.; Trivedi, Madhukar H.; Mehta, Jyutika A.

    2007-01-01

    The purpose of this study was to examine sensory quadrants in autism based on Dunn's Theory of Sensory Processing. The data for this study was collected as part of a cross-sectional study that examined sensory processing (using the Sensory Profile) in 103 persons with autism, 3-43 years of age, compared to 103 age- and gender-matched community…

  12. EFFECTS OF DOMINANCE AND CONTROL ON READING ACHIEVEMENT.

    ERIC Educational Resources Information Center

    BOOS, ROBERT W.; HILLERICH, ROBERT L.

    TWO DISPARATE STUDIES WERE REPLICATED WITH A PUBLIC SCHOOL POPULATION USED BY HILLERICH IN A 4-YEAR STUDY OF THE DEVELOPMENT OF HANDEDNESS AND EYEDNESS. SUBJECTS WERE 273 SEVENTH AND EIGHTH GRADERS WHO REMAINED FROM AN ORIGINAL POPULATION OF 400. TESTS WERE ADMINISTERED TO DETERMINE EYE DOMINANCE, HANDEDNESS, CONTROLLING EYE, READING ACHIEVEMENT,…

  13. The optic chiasm: a turning point in the evolution of eye/hand coordination

    PubMed Central

    2013-01-01

    The primate visual system has a uniquely high proportion of ipsilateral retinal projections, retinal ganglial cells that do not cross the midline in the optic chiasm. The general assumption is that this developed due to the selective advantage of accurate depth perception through stereopsis. Here, the hypothesis that the need for accurate eye-forelimb coordination substantially influenced the evolution of the primate visual system is presented. Evolutionary processes may change the direction of retinal ganglial cells. Crossing, or non-crossing, in the optic chiasm determines which hemisphere receives visual feedback in reaching tasks. Each hemisphere receives little tactile and proprioceptive information about the ipsilateral hand. The eye-forelimb hypothesis proposes that abundant ipsilateral retinal projections developed in the primate brain to synthesize, in a single hemisphere, visual, tactile, proprioceptive, and motor information about a given hand, and that this improved eye-hand coordination and optimized the size of the brain. If accurate eye-hand coordination was a major factor in the evolution of stereopsis, stereopsis is likely to be highly developed for activity in the area where the hands most often operate. The primate visual system is ideally suited for tasks within arm’s length and in the inferior visual field, where most manual activity takes place. Altering of ocular dominance in reaching tasks, reduced cross-modal cuing effects when arms are crossed, response of neurons in the primary motor cortex to viewed actions of a hand, multimodal neuron response to tactile as well as visual events, and extensive use of multimodal sensory information in reaching maneuvers support the premise that benefits of accurate limb control influenced the evolution of the primate visual system. The eye-forelimb hypothesis implies that evolutionary change toward hemidecussation in the optic chiasm provided parsimonious neural pathways in animals developing frontal vision and visually guided forelimbs, and also suggests a new perspective on vision convergence in prey and predatory animals. PMID:23866932

  14. Eye Movements of Flatfish for Different Gravity Condition

    NASA Astrophysics Data System (ADS)

    Iwata, Kaori; Takabayashi, Akira; Imada, Hideki; Miyachi, Ei-Ichi

    On Earth, gravity sensation plays a basic role for all of physiological phenomena in every creature. In microgravity, loss of gravity input causes many functional disorders in animals and humans. During adaptation to microgravity, otolith-mediated response such as eye movements would alter. Flatfish provide a natural model for the study of adaptive changes in the vestibuloocular reflex. During metamorphosis, vestibular and oculomotor coordinate of flatfish displaced 90 degrees about the longitudinal body axis. Therefore, it is expected that microgravity induce the sensory mismatch in adult flatfish. In this study, we analyzed the eye movements of normal and otolith removed flatfish for body tilting and the eye movements of normal flatfish during microgravity produced by parabolic aircraft flight. The fish was fixed on the tilting table controlled by computer. The eye movements for body tilting along the different body axis were video-recorded. The vertical and torsional eye rotations were analyzed frame by frame. In normal flatfish, torsional eye movements were larger for head up or head down tilting than leftward or rightward tilting. On the other hand, vertical eye movements were larger for leftward or rightward tilting than head up or head down tilting. After removal of left side utlicular otolith, the vertical eye movement for 180 degrees body tilting disappeared. For the changes of gravity, vertical eye movements were observed. These results suggested that eye movements of flatfish adapted to Earth's gravity condition and sacculus and lagena might play important role for otolith-ocular eye movements.

  15. Billie's eyes.

    PubMed

    Dunning, S E

    1993-03-01

    The author, a nurse, is personally opposed to abortion; however, her earlier encounter with a victim of an illegal abortion has prevented her from joining campaigns to reinstate bans on abortion rights. The woman, "Billie," presented to an inner-city Chicago hospital in 1970 with hemorrhaging. She had delayed going for treatment because she feared being imprisoned for having obtained an abortion. She rapidly entered septic shock, with hypotension, confusion, and hallucinations. Physicians removed her infected uterus and ovaries. Subsequent kidney failure necessitated the transfer of this young woman to another hospital where she could receive dialysis. The author was unable to obtain follow-up information on whether Billie survived. She remains haunted by the memory of Billie's wide, frightened eyes as she was placed in the ambulance. It is this memory, and the knowledge that desperate women like Billie will find someone, somewhere to perform an illegal abortion, that is behind the author's reluctant support for the right to choose. PMID:8442475

  16. Manual tracking enhances smooth pursuit eye movements

    PubMed Central

    Niehorster, Diederick C.; Siu, Wilfred W. F.; Li, Li

    2015-01-01

    Previous studies have reported that concurrent manual tracking enhances smooth pursuit eye movements only when tracking a self-driven or a predictable moving target. Here, we used a control-theoretic approach to examine whether concurrent manual tracking enhances smooth pursuit of an unpredictable moving target. In the eye-hand tracking condition, participants used their eyes to track a Gaussian target that moved randomly along a horizontal axis. In the meantime, they used their dominant hand to move a mouse to control the horizontal movement of a Gaussian cursor to vertically align it with the target. In the eye-alone tracking condition, the target and cursor positions recorded in the eye-hand tracking condition were replayed, and participants only performed eye tracking of the target. Catch-up saccades were identified and removed from the recorded eye movements, allowing for a frequency-response analysis of the smooth pursuit response to unpredictable target motion. We found that the overall smooth pursuit gain was higher and the number of catch-up saccades made was less when eye tracking was accompanied by manual tracking than when not. We conclude that concurrent manual tracking enhances smooth pursuit. This enhancement is a fundamental property of eye-hand coordination that occurs regardless of the predictability of the target motion. PMID:26605840

  17. Hereditary sensory neuropathy type I.

    PubMed

    Auer-Grumbach, Michaela

    2008-01-01

    Hereditary sensory neuropathy type I (HSN I) is a slowly progressive neurological disorder characterised by prominent predominantly distal sensory loss, autonomic disturbances, autosomal dominant inheritance, and juvenile or adulthood disease onset. The exact prevalence is unknown, but is estimated as very low. Disease onset varies between the 2nd and 5th decade of life. The main clinical feature of HSN I is the reduction of sensation sense mainly distributed to the distal parts of the upper and lower limbs. Variable distal muscle weakness and wasting, and chronic skin ulcers are characteristic. Autonomic features (usually sweating disturbances) are invariably observed. Serious and common complications are spontaneous fractures, osteomyelitis and necrosis, as well as neuropathic arthropathy which may even necessitate amputations. Some patients suffer from severe pain attacks. Hypacusis or deafness, or cough and gastrooesophageal reflux have been observed in rare cases. HSN I is a genetically heterogenous condition with three loci and mutations in two genes (SPTLC1 and RAB7) identified so far. Diagnosis is based on the clinical observation and is supported by a family history. Nerve conduction studies confirm a sensory and motor neuropathy predominantly affecting the lower limbs. Radiological studies, including magnetic resonance imaging, are useful when bone infections or necrosis are suspected. Definitive diagnosis is based on the detection of mutations by direct sequencing of the SPTLC1 and RAB7 genes. Correct clinical assessment and genetic confirmation of the diagnosis are important for appropriate genetic counselling and prognosis. Differential diagnosis includes the other hereditary sensory and autonomic neuropathies (HSAN), especially HSAN II, as well as diabetic foot syndrome, alcoholic neuropathy, neuropathies caused by other neurotoxins/drugs, immune mediated neuropathy, amyloidosis, spinal cord diseases, tabes dorsalis, lepra neuropathy, or decaying skin tumours like amelanotic melanoma. Management of HSN I follows the guidelines given for diabetic foot care (removal of pressure to the ulcer and eradication of infection, followed by the use of specific protective footwear) and starts with early and accurate counselling of patients about risk factors for developing foot ulcerations. The disorder is slowly progressive and does not influence life expectancy but is often severely disabling after a long duration of the disease. PMID:18348718

  18. Secondary eyes mediate the response to looming objects in jumping spiders (Phidippus audax, Salticidae)

    PubMed Central

    Spano, Lauren; Long, Skye M.; Jakob, Elizabeth M.

    2012-01-01

    Some species have sensory systems divided into subsystems with morphologically different sense organs that acquire different types of information within the same modality. Jumping spiders (family Salticidae) have eight eyes. Four eyes are directed anteriorly to view objects in front of the spider: a pair of principal eyes track targets with their movable retinae, while the immobile anterior lateral (AL) eyes have a larger field of view and lower resolution. To test whether the principal eyes, the AL eyes, or both together mediate the response to looming stimuli, we presented spiders with a video of a solid black circle that rapidly expanded (loomed) or contracted (receded). Control spiders and spiders with their principal eyes masked were significantly more likely to back away from the looming stimulus than were spiders with their AL eyes masked. Almost no individuals backed away from the receding stimulus. Our results show that the AL eyes alone mediate the loom response to objects anterior to the spider. PMID:23075526

  19. Childhood Eye Diseases and Conditions

    MedlinePLUS

    ... to 60 Adults Over 60 Babies, Children & Teenagers Computer Usage Diabetes Diet & Nutrition Eye Injuries Eye Screening ... Topics Preventing Eye Injuries Healthy Eyes During Pregnancy Computer Usage & Eye Strain Maintaining Your Sight with Diabetes ...

  20. Eye muscle repair - series (image)

    MedlinePLUS

    ... the eyeball to the eye socket. The external muscles of the eye are found behind the conjunctiva. ... The extraocular muscles of the eye (external to the eyeball) control the positioning of the eyes. They coordinate of the eye ...

  1. Regulation of eye development by frizzled signaling in Xenopus

    PubMed Central

    Rasmussen, Jennifer T.; Deardorff, Matthew A.; Tan, Change; Rao, Mahendra S.; Klein, Peter S.; Vetter, Monica L.

    2001-01-01

    Eye development in both invertebrates and vertebrates is regulated by a network of highly conserved transcription factors. However, it is not known what controls the expression of these factors to regulate early eye formation and whether transmembrane signaling events are involved. Here we establish a role for signaling via a member of the frizzled family of receptors in regulating early eye development. We show that overexpression of Xenopus frizzled 3 (Xfz3), a receptor expressed during normal eye development, functions cell autonomously to promote ectopic eye formation and can perturb endogenous eye development. Ectopic eyes obtained with Xfz3 overexpression have a laminar organization similar to that of endogenous eyes and contain differentiated retinal cell types. Ectopic eye formation is preceded by ectopic expression of transcription factors involved in early eye development, including Pax6, Rx, and Otx2. Conversely, targeted overexpression of a dominant-negative form of Xfz3 (Nxfz3), consisting of the soluble extracellular domain of the receptor, results in suppression of endogenous Pax6, Rx, and Otx2 expression and suppression of endogenous eye development. This effect can be rescued by coexpression of Xfz3. Finally, overexpression of Kermit, a protein that interacts with the C-terminal intracellular domain of Xfz3, also blocks endogenous eye development, suggesting that signaling through Xfz3 or a related receptor is required for normal eye development. In summary, we show that frizzled signaling is both necessary and sufficient to regulate eye development in Xenopus. PMID:11274406

  2. Eating for Your Eyes

    ERIC Educational Resources Information Center

    Stastny, Sherri Nordstrom; Garden-Robinson, Julie

    2011-01-01

    An educational program targeting older adults was developed to increase knowledge regarding nutrition and eye health. With age, the chance for eye disease increases, so prevention is critical. The Eating for Your Eyes program has promoted behavior changes regarding eye health among the participants. This program is easily replicated and use is…

  3. Eating for Your Eyes

    ERIC Educational Resources Information Center

    Stastny, Sherri Nordstrom; Garden-Robinson, Julie

    2011-01-01

    An educational program targeting older adults was developed to increase knowledge regarding nutrition and eye health. With age, the chance for eye disease increases, so prevention is critical. The Eating for Your Eyes program has promoted behavior changes regarding eye health among the participants. This program is easily replicated and use is…

  4. The ascidian pigmented sensory organs: structures and developmental programs.

    PubMed

    Esposito, R; Racioppi, C; Pezzotti, M R; Branno, M; Locascio, A; Ristoratore, F; Spagnuolo, A

    2015-01-01

    The recent advances on ascidian pigment sensory organ development and function represent a fascinating platform to get insight on the basic programs of chordate eye formation. This review aims to summarize current knowledge, at the structural and molecular levels, on the two main building blocks of ascidian light sensory organ, i.e. pigment cells and photoreceptor cells. The unique features of these structures (e.g., simplicity and well characterized cell lineage) are indeed making it possible to dissect the developmental programs at single cell resolution and will soon provide a panel of molecular tools to be exploited for a deep developmental and comparative-evolutionary analysis. PMID:25382437

  5. Mental Imagery as Revealed by Eye Movements and Spoken Predicates: A Test of Neurolinguistic Programming.

    ERIC Educational Resources Information Center

    Elich, Matthew; And Others

    1985-01-01

    Tested Bandler and Grinder's proposal that eye movement direction and spoken predicates are indicative of sensory modality of imagery. Subjects reported images in the three modes, but no relation between imagery and eye movements or predicates was found. Visual images were most vivid and often reported. Most subjects rated themselves as visual,…

  6. Evolution of sensory specializations in insectivores.

    PubMed

    Catania, Kenneth C

    2005-11-01

    Although insectivores have traditionally been thought of as primitive mammals with few specializations, recent studies have revealed great diversity in the sensory systems and brain organization of members of this mammalian order. The present article reviews some of these findings in three insectivore families that are thought to form a monophyletic group. These include hedgehogs (Erinaceidae), moles (Talpidae), and shrews (Soricidae). Members of each group live in unique ecological niches, have differently specialized senses, and exhibit different behaviors. Hedgehogs have well-developed visual, auditory, and somatosensory systems. Shrews make use of visual and auditory cues, but appear to depend most heavily on touch, particularly through prominent vibrissae. Moles are somatosensory specialists with small eyes and ears and unique epidermal mechanoreceptors called Eimer's organs used to identify prey and investigate their environment. In contrast to historical views of the insectivore order, members of this group have discrete and well-organized cortical sensory areas with sharp borders as determined from both electrophysiological mapping and analysis of cortical histology. Comparison of cortical organization across species reveals a number of specializations, including expansion of cortical representations of important sensory surfaces, the addition of cortical areas to some processing networks, and the subdivision of areas into separate cortical modules. In the case of the star-nosed mole, the somatosensory system has a tactile fovea and shares a number of features in common with the visual systems of sighted mammals. PMID:16215983

  7. Recognizing and Treating Eye Injuries

    MedlinePLUS

    ... Screening Guidelines Home Remedies for Simple Eye Problems Medical Marijuana for Glaucoma Pregnancy Preventing Eye Injuries Smokers Sports Using Eye Makeup Veterans What Is an Ophthalmologist? Your Eyes & the Sun Eye Health News Consumer Alerts ... an eye injury does occur, have an ophthalmologist or other medical doctor examine the eye as soon as possible, ...

  8. Our Sensory World.

    ERIC Educational Resources Information Center

    Liesman, C.; Barringer, M. D.

    The booklet explores the role of sensory experiences in the severely developmentally disabled child. Developmental theory is addressed, followed by specific activity suggestions (broken down into developmental levels) for developing tactile sense, auditory sense, gustatory (taste) sense, olfactory sense, visual sense, and kinesthetic sense.…

  9. Structured Sensory Trauma Interventions

    ERIC Educational Resources Information Center

    Steele, William; Kuban, Caelan

    2010-01-01

    This article features the National Institute of Trauma and Loss in Children (TLC), a program that has demonstrated via field testing, exploratory research, time series studies, and evidence-based research studies that its Structured Sensory Intervention for Traumatized Children, Adolescents, and Parents (SITCAP[R]) produces statistically…

  10. Recording Sensory Words

    ERIC Educational Resources Information Center

    Ashbrook, Peggy

    2007-01-01

    From children's viewpoints, what they experience in the world is what the world is like--for everyone. "What do others experience with their senses when they are in the same situation?" is a question that young children can explore by collecting data as they use a "feely box," or take a "sensory walk." There are many ways to focus the children's…

  11. Structured Sensory Trauma Interventions

    ERIC Educational Resources Information Center

    Steele, William; Kuban, Caelan

    2010-01-01

    This article features the National Institute of Trauma and Loss in Children (TLC), a program that has demonstrated via field testing, exploratory research, time series studies, and evidence-based research studies that its Structured Sensory Intervention for Traumatized Children, Adolescents, and Parents (SITCAP[R]) produces statistically…

  12. Recording Sensory Words

    ERIC Educational Resources Information Center

    Ashbrook, Peggy

    2007-01-01

    From children's viewpoints, what they experience in the world is what the world is like--for everyone. "What do others experience with their senses when they are in the same situation?" is a question that young children can explore by collecting data as they use a "feely box," or take a "sensory walk." There are many ways to focus the children's…

  13. Environmental Awareness (Sensory Awareness).

    ERIC Educational Resources Information Center

    Carpenter, Marian

    Capitalizing on the resources available within a city block, this resource guide for the emotionally handicapped (K-6) describes methods and procedures for developing sensory awareness in the urban out-of-doors. Conceptual focus is on interdependency ("living things are interdependent"). Involvement in the environment (observing, thinking, doing)…

  14. Studying Sensory Perception.

    ERIC Educational Resources Information Center

    Ackerly, Spafford C.

    2001-01-01

    Explains the vestibular organ's role in balancing the body and stabilizing the visual world using the example of a hunter. Describes the relationship between sensory perception and learning. Recommends using optical illusions to illustrate the distinctions between external realities and internal perceptions. (Contains 13 references.) (YDS)

  15. Modulating ocular dominance in the adult in real time.

    PubMed

    Hess, Robert; Zhou, Jiawei; Reynaud, Alexandre

    2015-09-01

    Using a dichoptic spatial phase combination paradigm that assesses the relative contribution that each eye makes to the binocular percept (ocular dominance), we have shown previously that 2.5 hours of patching, be it opaque or translucent, can result in a short-term enhancement of the patched eye's contribution to binocularity. This suggests that it is differential pattern deprivation, rather than the differential luminance deprivation that is driving this ocular dominance change. Here we ask what aspects of the pattern stimulation are important for ocular dominance. Observers dichoptically viewed movies of 2-3 hrs duration in which the spatial information in one eye's view had been altered (pattern deprivation). We measured each eye's contribution to the binocular percept before and after movie viewing using the dichoptic spatial phase task. Scrambling the spatial phases in one eye's view had no effect on ocular dominance, suggesting features constructed from phase-aligned components are unimportant in this regard. At the level at which these changes in dominance occurs only the Fourier amplitude spectrum is important. To verify this we show that graded changes to the magnitude of the amplitude spectrum result in graded changes in ocular dominance. To ascertain whether different parts of the amplitude spectrum are more important than others, we compared highpass with lowpass filtering and show that only the latter affects dominance. Finally, the ocular dominance change is not orientationally-dependent, suggesting the underlying mechanism is isotropic. Short-term changes in ocular dominance in adults can be obtained by altering the contrast of isotropic, high spatial frequency components seen by one eye. Meeting abstract presented at VSS 2015. PMID:26326515

  16. Understanding Sensory Integration. ERIC Digest.

    ERIC Educational Resources Information Center

    DiMatties, Marie E.; Sammons, Jennifer H.

    This brief paper summarizes what is known about sensory integration and sensory integration dysfunction (DSI). It outlines evaluation of DSI, treatment approaches, and implications for parents and teachers, including compensatory strategies for minimizing the impact of DSI on a child's life. Review of origins of sensory integration theory in the…

  17. Visual guidance of smooth pursuit eye movements: sensation, action, and what happens in between

    PubMed Central

    Lisberger, Stephen G.

    2010-01-01

    Smooth pursuit eye movements transform 100 ms of visual motion into a rapid initiation of smooth eye movement followed by sustained accurate tracking. Both the mean and variation of the visually-driven pursuit response, can be accounted for by the combination of the mean tuning curves and the correlated noise within the sensory representation of visual motion in extrastriate visual area MT. Sensory-motor and motor circuits have both housekeeping and modulatory functions, implemented in the cerebellum and the smooth eye movement region of the frontal eye fields. The representation of pursuit is quite different in these two regions of the brain, but both regions seem to control pursuit directly with little or no noise added downstream. Finally, pursuit exhibits a number of voluntary characteristics that happen on short time scales. These features make pursuit an excellent exemplar for understanding the general properties of sensory-motor processing in the brain. PMID:20510853

  18. The eyes of trilobites: The oldest preserved visual system.

    PubMed

    Clarkson, Euan; Levi-Setti, Riccardo; Horváth, Gabor

    2006-12-01

    The oldest preserved visual systems are to be found in the extinct trilobites, marine euarthropods which existed between about 520 and 250 million years ago. Because they possessed a calcified cuticle, they have a good fossil record, and commonly the lens-bearing surfaces of their paired compound eyes are well preserved. The sublensar structures, however, remain unknown. Three kinds of eyes have been distinguished. Holochroal eyes, apomorphic for trilobites, typically have many contiguous small lenses, set on a kidney-shaped visual surface. Lens optics, angular range of vision, and ontogeny have been established for many compound eyes. Some pelagic trilobites have enormous eyes, subtending a panoramic field of view. Schizochroal eyes are found only in one group, the phacopids (Ordovician to Devonian). These have large lenses, separated from each other by cuticular material, and the lenses have a complex doublet or triplet internal structure, which could focus light sharply. The optics of phacopid eyes are becoming increasingly well known despite the fact that there are no direct counterparts in any living arthropods today. Schizochroal eyes are apomorphic for phacopids and were derived by paedomorphosis from a holochroal precursor. Abathochroal eyes are confined to a short-lived Cambrian group, the eodiscids (of which most representatives were blind). Less is known about them than other trilobite eyes and their origins remain obscure. Some trilobite groups had no eyes, but had other kinds of sensory organs. In Upper Devonian times several groups of trilobites independently underwent progressive eye-reduction leading to blindness, related to prevailing environmental conditions of the time. The last trilobites (of Carboniferous and Permian age), however, had normal holochroal eyes, which persisted until the final extinction of trilobites at the end of the Permian. PMID:18089074

  19. Pink Eye (Conjunctivitis)

    MedlinePLUS

    ... rashes clinical tools newsletter | contact Share | Pink Eye (Conjunctivitis) Information for adults A A A This is the most typical appearance of conjunctivitis with redness of the eye and mucoid debris ...

  20. Diabetes - eye care

    MedlinePLUS

    Diabetes can harm your eyes. It can damage the small blood vessels in your retina, which is ... your eye. This condition is called diabetic retinopathy. Diabetes also increases your risk of having glaucoma, cataracts, ...

  1. Anatomy of the Eye

    MedlinePLUS

    ... Eye Terms Conditions Frequently Asked Questions Español Condiciones Chinese Conditions Anatomy of the Eye En Español Read in Chinese External (Extraocular) Anatomy Extraocular Muscles: There are six ...

  2. Aging and Your Eyes

    MedlinePLUS

    ... see or everything looks blurry See flashes of light Have eye pain Experience double vision Have redness ... see many new floaters and/or flashes of light, see your eye care professional right away. Tearing ( ...

  3. Eye Injuries at Home

    MedlinePLUS

    ... Guidelines Home Remedies for Simple Eye Problems Medical Marijuana for Glaucoma Pregnancy Preventing Eye Injuries Smokers Sports ... foods can that can splatter hot grease or oil. Opening champagne bottles during a celebration. Drilling or ...

  4. Down Syndrome: Eye Problems

    MedlinePLUS

    ... life expectancy. Do children with Down syndrome have eye problems? Individuals with Down syndrome are at increased ... When should children with Down syndrome receive an eye exam? The American Academy of Pediatrics recommends that ...

  5. Fluorescein eye stain

    MedlinePLUS

    ... surface of the cornea. The tear film contains water, oil, and mucus to protect and lubricate the eye. The health care provider then shines a blue light at your eye. Any problems on the surface ...

  6. National Eye Institute

    MedlinePLUS

    ... Watch the videos What’s New in Lens and Cataract Research? Houmam Araj, Ph.D., briefed the National ... Eye Council on the state of lens and cataract research funded by NEI. Watch the Video Eye ...

  7. Task-specific transfer of perceptual learning across sensory modalities.

    PubMed

    McGovern, David P; Astle, Andrew T; Clavin, Sarah L; Newell, Fiona N

    2016-01-11

    It is now widely accepted that primary cortical areas of the brain that were once thought to be sensory-specific undergo significant functional reorganisation following sensory deprivation. For instance, loss of vision or audition leads to the brain areas normally associated with these senses being recruited by the remaining sensory modalities [1]. Despite this, little is known about the rules governing crossmodal plasticity in people who experience typical sensory development, or the potential behavioural consequences. Here, we used a novel perceptual learning paradigm to assess whether the benefits associated with training on a task in one sense transfer to another sense. Participants were randomly assigned to a spatial or temporal task that could be performed visually or aurally, which they practiced for five days; before and after training, we measured discrimination thresholds on all four conditions and calculated the extent of transfer between them. Our results show a clear transfer of learning between sensory modalities; however, generalisation was limited to particular conditions. Specifically, learned improvements on the spatial task transferred from the visual domain to the auditory domain, but not vice versa. Conversely, benefits derived from training on the temporal task transferred from the auditory domain to visual domain, but not vice versa. These results suggest a unidirectional transfer of perceptual learning from dominant to non-dominant sensory modalities and place important constraints on models of multisensory processing and plasticity. PMID:26766225

  8. The interaction of Bayesian priors and sensory data and its neural circuit implementation in visually-guided movement

    PubMed Central

    Yang, Jin; Lee, Joonyeol; Lisberger, Stephen G.

    2012-01-01

    Sensory-motor behavior results from a complex interaction of noisy sensory data with priors based on recent experience. By varying the stimulus form and contrast for the initiation of smooth pursuit eye movements in monkeys, we show that visual motion inputs compete with two independent priors: one prior biases eye speed toward zero; the other prior attracts eye direction according to the past several days’ history of target directions. The priors bias the speed and direction of the initiation of pursuit for the weak sensory data provided by the motion of a low-contrast sine wave grating. However, the priors have relatively little effect on pursuit speed and direction when the visual stimulus arises from the coherent motion of a high-contrast patch of dots. For any given stimulus form, the mean and variance of eye speed co-vary in the initiation of pursuit, as expected for signal-dependent noise. This relationship suggests that pursuit implements a trade-off between movement accuracy and variation, reducing both when the sensory signals are noisy. The tradeoff is implemented as a competition of sensory data and priors that follows the rules of Bayesian estimation. Computer simulations show that the priors can be understood as direction specific control of the strength of visual-motor transmission, and can be implemented in a neural-network model that makes testable predictions about the population response in the smooth eye movement region of the frontal eye fields. PMID:23223286

  9. The interaction of bayesian priors and sensory data and its neural circuit implementation in visually guided movement.

    PubMed

    Yang, Jin; Lee, Joonyeol; Lisberger, Stephen G

    2012-12-01

    Sensory-motor behavior results from a complex interaction of noisy sensory data with priors based on recent experience. By varying the stimulus form and contrast for the initiation of smooth pursuit eye movements in monkeys, we show that visual motion inputs compete with two independent priors: one prior biases eye speed toward zero; the other prior attracts eye direction according to the past several days' history of target directions. The priors bias the speed and direction of the initiation of pursuit for the weak sensory data provided by the motion of a low-contrast sine wave grating. However, the priors have relatively little effect on pursuit speed and direction when the visual stimulus arises from the coherent motion of a high-contrast patch of dots. For any given stimulus form, the mean and variance of eye speed covary in the initiation of pursuit, as expected for signal-dependent noise. This relationship suggests that pursuit implements a trade-off between movement accuracy and variation, reducing both when the sensory signals are noisy. The tradeoff is implemented as a competition of sensory data and priors that follows the rules of Bayesian estimation. Computer simulations show that the priors can be understood as direction-specific control of the strength of visual-motor transmission, and can be implemented in a neural-network model that makes testable predictions about the population response in the smooth eye movement region of the frontal eye fields. PMID:23223286

  10. Construction of special eye models for investigation of chromatic and higher-order aberrations of eyes.

    PubMed

    Zhai, Yi; Wang, Yan; Wang, Zhaoqi; Liu, Yongji; Zhang, Lin; He, Yuanqing; Chang, Shengjiang

    2014-01-01

    An achromatic element eliminating only longitudinal chromatic aberration (LCA) while maintaining transverse chromatic aberration (TCA) is established for the eye model, which involves the angle formed by the visual and optical axis. To investigate the impacts of higher-order aberrations on vision, the actual data of higher-order aberrations of human eyes with three typical levels are introduced into the eye model along visual axis. Moreover, three kinds of individual eye models are established to investigate the impacts of higher-order aberrations, chromatic aberration (LCA+TCA), LCA and TCA on vision under the photopic condition, respectively. Results show that for most human eyes, the impact of chromatic aberration on vision is much stronger than that of higher-order aberrations, and the impact of LCA in chromatic aberration dominates. The impact of TCA is approximately equal to that of normal level higher-order aberrations and it can be ignored when LCA exists. PMID:25227016

  11. Eye Injuries (For Parents)

    MedlinePLUS

    ... the eye lasting eye pain any changes in vision any visible abnormality of the eyeball visible bleeding on the white part (sclera) of the eye, especially near the cornea If the injury happened during one of your child's routine activities, such as a sport , follow up by investing in an ounce of ...

  12. Dwarf Eye Disorder

    ERIC Educational Resources Information Center

    Science Teacher, 2005

    2005-01-01

    Johns Hopkins researchers at the Wilmer Eye Institute have discovered what appears to be the first human gene mutation that causes extreme farsightedness. The researchers report that nanophthalmos, Greek for "dwarf eye," is a rare, potentially blinding disorder caused by an alteration in a gene called MFRP that helps control eye growth and…

  13. Instabilities in sensory processes

    NASA Astrophysics Data System (ADS)

    Balakrishnan, J.

    2014-07-01

    In any organism there are different kinds of sensory receptors for detecting the various, distinct stimuli through which its external environment may impinge upon it. These receptors convey these stimuli in different ways to an organism's information processing region enabling it to distinctly perceive the varied sensations and to respond to them. The behavior of cells and their response to stimuli may be captured through simple mathematical models employing regulatory feedback mechanisms. We argue that the sensory processes such as olfaction function optimally by operating in the close proximity of dynamical instabilities. In the case of coupled neurons, we point out that random disturbances and fluctuations can move their operating point close to certain dynamical instabilities triggering synchronous activity.

  14. Eye movements in depth to visual illusions

    NASA Astrophysics Data System (ADS)

    Wismeijer, D. A.

    2009-10-01

    We perceive the three-dimensional (3D) environment that surrounds us with deceptive effortlessness. In fact, we are far from comprehending how the visual system provides us with this stable perception of the (3D) world around us. This thesis will focus on the interplay between visual perception of depth and its closely related action system, eye movements in depth. The human visual system is comprised of a sensory (input) and an output (motor) system. Processed information from the sensory system can result in two explicit measurable response types: conscious visual perception and ocular motor behavior. It is still a matter of debate whether conscious visual perception and action (including hand- and arm-movements) use the same information or whether the visual system has separate channels processing information for perception and action. In this thesis, we study (1) if separate channels, one for eye movements and one for conscious visual perception, indeed exist, and (2) if so, if there is a direct input from the perceptual pathway to the motor pathway. Assuming that either eye movements and conscious visual perception are based on information from a common source (a negative answer to issue 1) or perception can directly influence, or guide, eye movements (an affirmative answer to research question 2), (eye) movements reflect our conscious visual perception. If so, eye movements could provide us with an alternative method to probe our conscious visual perception, making explicit perceptual reports superfluous. In this thesis we focus on depth perception and the two types of eye movements that are closest related to depth perception, namely vergence (an eye movement that gets a certain depth plane into focus) and saccades (a rapid eye movement to change gaze direction). Over the last 20 years it has been shown that depth perception is based on a weighted combination of depth cues available such as linear perspective, occlusion and binocular disparity. How eye movements are planned, however, is still unclear. Several studies have reported that eye movements are, to varying degrees, correlated with perception and thus concluded that perception guides eye movements. However, in most of these studies depth perception was correlated to the depth cues and a clear distinction between cues and perception could not be made. A way to make a dissociation between cues and perception, is to make use of depth reversal illusions: stimuli that can induce multiple equally likely depth interpretations while the stimulus cues remain the same. That means that perception can alternate, while cues remain constant leading to a dissociation between perception and cues. In several different studies we show that in the case of vergence, eye movements are planned based on depth cues (mainly disparity) and are uncorrelated to perception. In the case of saccades, we show that the direction of saccades is highly correlated to perception, but seems to be subserved by a separate system combining cues using very similar weights as for perception.

  15. Genes for Hereditary Sensory and Autonomic Neuropathies: A Genotype-Phenotype Correlation

    ERIC Educational Resources Information Center

    Rotthier, Annelies; Baets, Jonathan; De Vriendt, Els; Jacobs, An; Auer-Grumbach, Michaela; Levy, Nicolas; Bonello-Palot, Nathalie; Kilic, Sara Sebnem; Weis, Joachim; Nascimento, Andres; Swinkels, Marielle; Kruyt, Moyo C.; Jordanova, Albena; De Jonghe, Peter; Timmerman, Vincent

    2009-01-01

    Hereditary sensory and autonomic neuropathies (HSAN) are clinically and genetically heterogeneous disorders characterized by axonal atrophy and degeneration, exclusively or predominantly affecting the sensory and autonomic neurons. So far, disease-associated mutations have been identified in seven genes: two genes for autosomal dominant ("SPTLC1"…

  16. Genes for Hereditary Sensory and Autonomic Neuropathies: A Genotype-Phenotype Correlation

    ERIC Educational Resources Information Center

    Rotthier, Annelies; Baets, Jonathan; De Vriendt, Els; Jacobs, An; Auer-Grumbach, Michaela; Levy, Nicolas; Bonello-Palot, Nathalie; Kilic, Sara Sebnem; Weis, Joachim; Nascimento, Andres; Swinkels, Marielle; Kruyt, Moyo C.; Jordanova, Albena; De Jonghe, Peter; Timmerman, Vincent

    2009-01-01

    Hereditary sensory and autonomic neuropathies (HSAN) are clinically and genetically heterogeneous disorders characterized by axonal atrophy and degeneration, exclusively or predominantly affecting the sensory and autonomic neurons. So far, disease-associated mutations have been identified in seven genes: two genes for autosomal dominant ("SPTLC1"…

  17. Difference in visual processing assessed by eye vergence movements.

    PubMed

    Solé Puig, Maria; Puigcerver, Laura; Aznar-Casanova, J Antonio; Supèr, Hans

    2013-01-01

    Orienting visual attention is closely linked to the oculomotor system. For example, a shift of attention is usually followed by a saccadic eye movement and can be revealed by micro saccades. Recently we reported a novel role of another type of eye movement, namely eye vergence, in orienting visual attention. Shifts in visuospatial attention are characterized by the response modulation to a selected target. However, unlike (micro-) saccades, eye vergence movements do not carry spatial information (except for depth) and are thus not specific to a particular visual location. To further understand the role of eye vergence in visual attention, we tested subjects with different perceptual styles. Perceptual style refers to the characteristic way individuals perceive environmental stimuli, and is characterized by a spatial difference (local vs. global) in perceptual processing. We tested field independent (local; FI) and field dependent (global; FD) observers in a cue/no-cue task and a matching task. We found that FI observers responded faster and had stronger modulation in eye vergence in both tasks than FD subjects. The results may suggest that eye vergence modulation may relate to the trade-off between the size of spatial region covered by attention and the processing efficiency of sensory information. Alternatively, vergence modulation may have a role in the switch in cortical state to prepare the visual system for new incoming sensory information. In conclusion, vergence eye movements may be added to the growing list of functions of fixational eye movements in visual perception. However, further studies are needed to elucidate its role. PMID:24069140

  18. Difference in Visual Processing Assessed by Eye Vergence Movements

    PubMed Central

    Solé Puig, Maria; Puigcerver, Laura; Aznar-Casanova, J. Antonio; Supèr, Hans

    2013-01-01

    Orienting visual attention is closely linked to the oculomotor system. For example, a shift of attention is usually followed by a saccadic eye movement and can be revealed by micro saccades. Recently we reported a novel role of another type of eye movement, namely eye vergence, in orienting visual attention. Shifts in visuospatial attention are characterized by the response modulation to a selected target. However, unlike (micro-) saccades, eye vergence movements do not carry spatial information (except for depth) and are thus not specific to a particular visual location. To further understand the role of eye vergence in visual attention, we tested subjects with different perceptual styles. Perceptual style refers to the characteristic way individuals perceive environmental stimuli, and is characterized by a spatial difference (local vs. global) in perceptual processing. We tested field independent (local; FI) and field dependent (global; FD) observers in a cue/no-cue task and a matching task. We found that FI observers responded faster and had stronger modulation in eye vergence in both tasks than FD subjects. The results may suggest that eye vergence modulation may relate to the trade-off between the size of spatial region covered by attention and the processing efficiency of sensory information. Alternatively, vergence modulation may have a role in the switch in cortical state to prepare the visual system for new incoming sensory information. In conclusion, vergence eye movements may be added to the growing list of functions of fixational eye movements in visual perception. However, further studies are needed to elucidate its role. PMID:24069140

  19. The social dominance paradox.

    PubMed

    Cook, Jennifer Louise; den Ouden, Hanneke E M; Heyes, Cecilia M; Cools, Roshan

    2014-12-01

    Dominant individuals report high levels of self-sufficiency, self-esteem, and authoritarianism. The lay stereotype suggests that such individuals ignore information from others, preferring to make their own choices. However, the nonhuman animal literature presents a conflicting view, suggesting that dominant individuals are avid social learners, whereas subordinates focus on learning from private experience. Whether dominant humans are best characterized by the lay stereotype or the animal view is currently unknown. Here, we present a "social dominance paradox": using self-report scales and computerized tasks, we demonstrate that socially dominant people explicitly value independence, but, paradoxically, in a complex decision-making task, they show an enhanced reliance (relative to subordinate individuals) on social learning. More specifically, socially dominant people employed a strategy of copying other agents when the agents' responses had a history of being correct. However, in humans, two subtypes of dominance have been identified: aggressive and social. Aggressively dominant individuals, who are as likely to "get their own way" as socially dominant individuals but who do so through the use of aggressive or Machiavellian tactics, did not use social information, even when it was beneficial to do so. This paper presents the first study of dominance and social learning in humans and challenges the lay stereotype in which all dominant individuals ignore others' views. The more subtle perspective we offer could have important implications for decision making in both the boardroom and the classroom. PMID:25454588

  20. Measurement in Sensory Modulation: The Sensory Processing Scale Assessment

    PubMed Central

    Miller, Lucy J.; Sullivan, Jillian C.

    2014-01-01

    OBJECTIVE. Sensory modulation issues have a significant impact on participation in daily life. Moreover, understanding phenotypic variation in sensory modulation dysfunction is crucial for research related to defining homogeneous groups and for clinical work in guiding treatment planning. We thus evaluated the new Sensory Processing Scale (SPS) Assessment. METHOD. Research included item development, behavioral scoring system development, test administration, and item analyses to evaluate reliability and validity across sensory domains. RESULTS. Items with adequate reliability (internal reliability >.4) and discriminant validity (p < .01) were retained. Feedback from the expert panel also contributed to decisions about retaining items in the scale. CONCLUSION. The SPS Assessment appears to be a reliable and valid measure of sensory modulation (scale reliability >.90; discrimination between group effect sizes >1.00). This scale has the potential to aid in differential diagnosis of sensory modulation issues. PMID:25184464

  1. Phenomenological Dimensions of Sensory Gating

    PubMed Central

    Hetrick, William P.; Smith, David A.

    2012-01-01

    Contemporary sensory gating definitions are generally tied to the perceptual and attentional phenomenology described by McGhie and Chapman, including abnormalities in the quality of sensory input, heightened awareness of background noises, and poor selective attention reported by individuals with schizophrenia. Despite these explicit phenomenological origins, little is known about the experiential phenomena underlying contemporary operationalizations of the sensory gating construct, such as whether the construct is restricted to experiences associated with the modulation of sensory percepts includes selective attention and distractibility or even whether the construct is accessible via self-report. Because clarification of these issues has important implications for the development and testing of psychological theories and the study of psychopathology, a series of studies was conducted to (a) empirically identify the major dimensions of sensory gating–like perceptual and attentional phenomenology in healthy young adults and (b) develop a psychometrically sound self-report rating scale to capture these dimensions, the Sensory Gating Inventory (SGI). Factor analyses of Likert items measuring a broad range of sensory gating–like subjective experiences revealed 1 primary factor that encompassed anomalies of perceptual modulation (eg, perceptions of heightened stimulus sensitivity and sensory inundation) and 3 other factors measuring disturbances in the processes of focal and radial attention as well as exacerbation of sensory gating–like anomalies by fatigue and stress. Psychometrically, the SGI demonstrated strong reliability and validity. An empirically based conceptual demarcation of the sensory gating construct is offered, and directions for future research are described. PMID:20525773

  2. Training the Eyes for Competition: Fighting Eyes.

    ERIC Educational Resources Information Center

    Williams, Darrell; Bradford, Vincent

    1989-01-01

    Fencers should be taught to discipline their eyes to focus on the opponent's hand. The rationale for this strategy as well as drills to develop "hand watching" skills are presented in this article. (IAH)

  3. Photoreceptor Sensory Cilium: Traversing the Ciliary Gate

    PubMed Central

    Khanna, Hemant

    2015-01-01

    Cilia are antenna-like extensions of the plasma membrane found in nearly all cell types. In the retina of the eye, photoreceptors develop unique sensory cilia. Not much was known about the mechanisms underlying the formation and function of photoreceptor cilia, largely because of technical limitations and the specific structural and functional modifications that cannot be modeled in vitro. With recent advances in microscopy techniques and molecular and biochemical approaches, we are now beginning to understand the molecular basis of photoreceptor ciliary architecture, ciliary function and its involvement in human diseases. Here, I will discuss the studies that have revealed new knowledge of how photoreceptor cilia regulate their identity and function while coping with high metabolic and trafficking demands associated with processing light signal. PMID:26501325

  4. Sensory, motor, and combined contexts for context-specific adaptation of saccade gain in humans

    NASA Technical Reports Server (NTRS)

    Shelhamer, Mark; Clendaniel, Richard

    2002-01-01

    Saccadic eye movements can be adapted in a context-specific manner such that their gain can be made to depend on the state of a prevailing context cue. We asked whether context cues are more effective if their nature is primarily sensory, motor, or a combination of sensory and motor. Subjects underwent context-specific adaptation using one of three different context cues: a pure sensory context (head roll-tilt right or left); a pure motor context (changes in saccade direction); or a combined sensory-motor context (head roll-tilt and changes in saccade direction). We observed context-specific adaptation in each condition; the greatest degree of context-specificity occurred in paradigms that used the motor cue, alone or in conjunction with the sensory cue. Copyright 2002 Elsevier Science Ireland Ltd.

  5. Hawk Eyes I: Diurnal Raptors Differ in Visual Fields and Degree of Eye Movement

    PubMed Central

    O'Rourke, Colleen T.; Hall, Margaret I.; Pitlik, Todd; Fernández-Juricic, Esteban

    2010-01-01

    Background Different strategies to search and detect prey may place specific demands on sensory modalities. We studied visual field configuration, degree of eye movement, and orbit orientation in three diurnal raptors belonging to the Accipitridae and Falconidae families. Methodology/Principal Findings We used an ophthalmoscopic reflex technique and an integrated 3D digitizer system. We found inter-specific variation in visual field configuration and degree of eye movement, but not in orbit orientation. Red-tailed Hawks have relatively small binocular areas (∼33°) and wide blind areas (∼82°), but intermediate degree of eye movement (∼5°), which underscores the importance of lateral vision rather than binocular vision to scan for distant prey in open areas. Cooper's Hawks' have relatively wide binocular fields (∼36°), small blind areas (∼60°), and high degree of eye movement (∼8°), which may increase visual coverage and enhance prey detection in closed habitats. Additionally, we found that Cooper's Hawks can visually inspect the items held in the tip of the bill, which may facilitate food handling. American Kestrels have intermediate-sized binocular and lateral areas that may be used in prey detection at different distances through stereopsis and motion parallax; whereas the low degree eye movement (∼1°) may help stabilize the image when hovering above prey before an attack. Conclusions We conclude that: (a) there are between-species differences in visual field configuration in these diurnal raptors; (b) these differences are consistent with prey searching strategies and degree of visual obstruction in the environment (e.g., open and closed habitats); (c) variations in the degree of eye movement between species appear associated with foraging strategies; and (d) the size of the binocular and blind areas in hawks can vary substantially due to eye movements. Inter-specific variation in visual fields and eye movements can influence behavioral strategies to visually search for and track prey while perching. PMID:20877645

  6. The Intelligent Eye.

    ERIC Educational Resources Information Center

    Gregory, R. L.

    Based on the premise that perception is a continual series of simple hypotheses about the external world which are built up and selected by sensory experiences, this book explores in detail some of the major findings in perception and speculates about interconnections between sensory experiences, brain function, perception, and language and…

  7. Ocular dominance, cognitive strategy, and sex differences in spatial ability.

    PubMed

    Freedman, R J; Rovegno, L

    1981-04-01

    Ocular dominance, handedness, and cognitive strategy were assessed in relation to performance by 146 undergraduates on the Vandenberg Mental Rotation Test. Higher spatial scores were found for right-eyed subjects, right-handed subjects, and males. These higher scoring groups reported using similar cognitive strategies. The counted blocks less, used their hands less, and pictured in their minds more than the left-eyed, left-handed and female subjects. Results confirm previous findings. PMID:7255075

  8. Changes in sensory activity of ocular surface sensory nerves during allergic keratoconjunctivitis.

    PubMed

    Acosta, M Carmen; Luna, Carolina; Quirce, Susana; Belmonte, Carlos; Gallar, Juana

    2013-11-01

    Peripheral neural mechanisms underlying the sensations of irritation, discomfort, and itch accompanying the eye allergic response have not been hitherto analyzed. We explored this question recording the changes in the electrical activity of corneoconjunctival sensory nerve fibers of the guinea pig after an ocular allergic challenge. Sensitization was produced by i.p. ovalbumin followed by repeated application in the eye of 10% ovalbumin on days 14 to 18. Blinking and tearing rate were measured. Spontaneous and stimulus-evoked (mechanical, thermal, chemical) impulse activity was recorded from mechanonociceptor, polymodal nociceptor and cold corneoscleral sensory afferent fibers. After a single (day 14) or repeated daily exposures to the allergen during the following 3 to 4days, tearing and blinking rate increased significantly. Also, sensitization was observed in mechanonociceptors (transient reduction of mechanical threshold only on day 14) and in polymodal nociceptors (sustained enhancement of the impulse response to acidic stimulation). In contrast, cold thermoreceptors showed a significant decrease in basal ongoing activity and in the response to cooling. Treatment with the TRPV1 and TRPA1 blockers capsazepine and HC-030031 reversed the augmented blinking. Only capsazepine attenuated tearing rate increase and sensitization of the polymodal nociceptors response to CO2. Capsazepine also prevented the decrease in cold thermoreceptor activity caused by the allergic challenge. We conclude that changes in nerve impulse activity accompanying the ocular allergic response, primarily mediated by activation of nociceptor's TRPV1 and to a lesser degree by activation of TRPA1 channels, explain the eye discomfort sensations accompanying allergic episodes. PMID:23867735

  9. Phototaxis and the origin of visual eyes.

    PubMed

    Randel, Nadine; Jékely, Gáspár

    2016-01-01

    Vision allows animals to detect spatial differences in environmental light levels. High-resolution image-forming eyes evolved from low-resolution eyes via increases in photoreceptor cell number, improvements in optics and changes in the neural circuits that process spatially resolved photoreceptor input. However, the evolutionary origins of the first low-resolution visual systems have been unclear. We propose that the lowest resolving (two-pixel) visual systems could initially have functioned in visual phototaxis. During visual phototaxis, such elementary visual systems compare light on either side of the body to regulate phototactic turns. Another, even simpler and non-visual strategy is characteristic of helical phototaxis, mediated by sensory-motor eyespots. The recent mapping of the complete neural circuitry (connectome) of an elementary visual system in the larva of the annelid Platynereis dumerilii sheds new light on the possible paths from non-visual to visual phototaxis and to image-forming vision. We outline an evolutionary scenario focusing on the neuronal circuitry to account for these transitions. We also present a comprehensive review of the structure of phototactic eyes in invertebrate larvae and assign them to the non-visual and visual categories. We propose that non-visual systems may have preceded visual phototactic systems in evolution that in turn may have repeatedly served as intermediates during the evolution of image-forming eyes. PMID:26598725

  10. Eye movements: The past 25 years

    PubMed Central

    Kowler, Eileen

    2011-01-01

    This article reviews the past 25 of research on eye movements (1986–2011). Emphasis is on three oculomotor behaviors: gaze control, smooth pursuit and saccades, and on their interactions with vision. Focus over the past 25 years has remained on the fundamental and classical questions: What are the mechanisms that keep gaze stable with either stationary or moving targets? How does the motion of the image on the retina affect vision? Where do we look – and why – when performing a complex task? How can the world appear clear and stable despite continual movements of the eyes? The past 25 years of investigation of these questions has seen progress and transformations at all levels due to new approaches (behavioral, neural and theoretical) aimed at studying how eye movements cope with real-world visual and cognitive demands. The work has led to a better understanding of how prediction, learning and attention work with sensory signals to contribute to the effective operation of eye movements in visually rich environments. PMID:21237189

  11. Eye movements modulate visual receptive fields of V4 neurons.

    PubMed

    Tolias, A S; Moore, T; Smirnakis, S M; Tehovnik, E J; Siapas, A G; Schiller, P H

    2001-03-01

    The receptive field, defined as the spatiotemporal selectivity of neurons to sensory stimuli, is central to our understanding of the neuronal mechanisms of perception. However, despite the fact that eye movements are critical during normal vision, the influence of eye movements on the structure of receptive fields has never been characterized. Here, we map the receptive fields of macaque area V4 neurons during saccadic eye movements and find that receptive fields are remarkably dynamic. Specifically, before the initiation of a saccadic eye movement, receptive fields shrink and shift towards the saccade target. These spatiotemporal dynamics may enhance information processing of relevant stimuli during the scanning of a visual scene, thereby assisting the selection of saccade targets and accelerating the analysis of the visual scene during free viewing. PMID:11301034

  12. Electroconvulsive therapy and determination of cerebral dominance

    PubMed Central

    Dragovic, Milan; Allet, Lindsay; Janca, Aleksandar

    2004-01-01

    Electroconvulsive therapy (ECT) often results in a number of short- and long-time side effects including memory impairment for past and current events, which can last for several months after ECT treatment. It has been suggested that unilateral ECT (uECT) with electrodes placed over the non-dominant (typically right) hemisphere significantly reduces side effects, especially memory disturbances. It is important to note that cerebral dominance equates to speech dominance and avoiding this area of the brain also reduces speech dysfunction after ECT. Traditionally, the routine clinical determination of cerebral dominance has been through the assessment of hand, foot and eye dominance, which is an easy and inexpensive approach that, however, does not ensure accuracy. This review of literature on different methods and techniques for determination of cerebral dominance and provides evidence that functional transcranial Doppler sonography (fTCD) represents a valid and safe alternative to invasive techniques for identifying speech lateralisation. It can be concluded that fTCD, notwithstanding its costs, could be used as a standard procedure prior to uECT treatment to determine cerebral dominance, thereby further reducing cognitive side-effects of ECT and possibly making it more acceptable to both patients and clinicians. PMID:15306035

  13. Cortical oscillations and sensory predictions.

    PubMed

    Arnal, Luc H; Giraud, Anne-Lise

    2012-07-01

    Many theories of perception are anchored in the central notion that the brain continuously updates an internal model of the world to infer the probable causes of sensory events. In this framework, the brain needs not only to predict the causes of sensory input, but also when they are most likely to happen. In this article, we review the neurophysiological bases of sensory predictions of "what' (predictive coding) and 'when' (predictive timing), with an emphasis on low-level oscillatory mechanisms. We argue that neural rhythms offer distinct and adapted computational solutions to predicting 'what' is going to happen in the sensory environment and 'when'. PMID:22682813

  14. Cutaneous sensory disorder.

    PubMed

    Gupta, Madhulika A; Gupta, Aditya K

    2013-06-01

    Cutaneous sensory disorder (CSD) represents a heterogeneous clinical situation where the patient presents with either disagreeable skin sensations (ie, itching, burning, stinging) or pain (ie, allodynia) and/or negative sensory symptoms (ie, numbness, hypoaesthesia). These patients have no apparent diagnosable dermatologic or medical condition that explains the cutaneous symptom, and typically have negative findings upon medical workup. Skin regions that normally have a greater density of epidermal innervation tend to be more susceptible to the development of CSD. CSDs can affect any body region but generally tend to be confined to the face, scalp and perineum, and have been referred to in the literature with region-specific terms such as burning mouth syndrome, glossodynia and vulvodynia. Symptoms such as pruritus with unexplained hyperhidrosis may occur during sleep, as a result of heightened sympathetic tone. Sleep deprivation and insomnia can play a moderating role in CSD. Somatization and dissociation can play a central role in the pathogenesis of CSDs. A review of the literature suggests that CSDs represent a complex, and often poorly understood interplay between neurobiological factors associated with neuropathic pain, neuropathic itch and neurologic/neuropsychiatric states (eg, radiculopathies, stroke, depression and posttraumatic stress disorder). These neurologic/neuropsychiatric states can modulate pain and itch perception by potentially affecting the pain and itch pathways at a structural and/or functional level. PMID:24049969

  15. Towards Optogenetic Sensory Replacement

    PubMed Central

    Doroudchi, M. Mehdi; Greenberg, Kenneth P.; Zorzos, Anthony N.; Hauswirth, William W.; Fonstad, Clifton G.; Horsager, Alan; Boyden, Edward S.

    2013-01-01

    Over the last several years we have developed a rapidly-expanding suite of genetically-encoded reagents (e.g., ChR2, Halo, Arch, Mac, and others) that, when expressed in specific neuron types in the nervous system, enable their activities to be powerfully and precisely activated and silenced in response to light. If the genes that encode for these reagents can be delivered to cells in the body using gene therapy methods, and if the resultant protein payloads operate safely and effectively over therapeutically important periods of time, these molecules could subserve a set of precise prosthetics that use light as the trigger of information entry into the nervous system, e.g. for sensory replacement. Here we discuss the use of ChR2 to make the photoreceptor-deprived retina, as found in diseases such as retinitis pigmentosa, sensitive to light, enabling restoration of functional vision in a mouse model of blindness. We also discuss arrays of light sources that could be useful for delivering patterned sensory information into the nervous system. PMID:22255005

  16. The fellow eye.

    PubMed Central

    Mapstone, R

    1981-01-01

    The result of a 10-year longitudinal study of the fellow eye at risk of developing closed-angle glaucoma (because the presenting eye had the disease) is described. 202 eyes were observed between 1 August 1970 and 31 July 1980. Each eye was provoked shortly after presentation using a pilocarpine phenylephrine provocative test. If the test produced a closed-angle glaucoma an iridectomy was done; if closed-angle glaucoma did not occur the eye was observed and it was reprovoked at yearly intervals. There were 3 possible outcomes for any one eye. Either the eye developed closed-angle glaucoma; or it was lost to follow-up; or at the end of the study the patient was alive, under observation, without having developed glaucoma. 90% of acute attacks occurred within 6 months of presentation. If an eye survived the first year without getting glaucoma the probability of its development in any one year period up to the fifth anniversary was 0.05; thereafter it was zero. The cumulative probability of an eye surviving to the fifth anniversary without glaucoma was 0.34, remaining constant thereafter; that is 34% of iridectomies are unnecessary. A high prevalence of ocular hypertension was seen in eyes that did not have an iridectomy (26%). It was concluded that a routine iridectomy is not necessary and that the fellow eye that will get glaucoma can usually be detected. The untreated fellow eye presents a naturally occurring model of one of the mechanisms involved in the production of ocular hypertension. PMID:7260011

  17. Assessing Bilingual Dominance.

    ERIC Educational Resources Information Center

    Flege, James Emil; Mackay, Ian R. A.; Piske, Thorsten

    2002-01-01

    Used two methods to assess bilingual dominance in four groups of Italian-English bilinguals. Ratios were derived from bilinguals' self-rating of ability to speak and understand Italian compared to English. Dominance in Italian was associated with a relatively high level of performance in Italian (assessed in a translation task) and relatively poor…

  18. Genetic Dominance & Cellular Processes

    ERIC Educational Resources Information Center

    Seager, Robert D.

    2014-01-01

    In learning genetics, many students misunderstand and misinterpret what "dominance" means. Understanding is easier if students realize that dominance is not a mechanism, but rather a consequence of underlying cellular processes. For example, metabolic pathways are often little affected by changes in enzyme concentration. This means that…

  19. Genetic Dominance & Cellular Processes

    ERIC Educational Resources Information Center

    Seager, Robert D.

    2014-01-01

    In learning genetics, many students misunderstand and misinterpret what "dominance" means. Understanding is easier if students realize that dominance is not a mechanism, but rather a consequence of underlying cellular processes. For example, metabolic pathways are often little affected by changes in enzyme concentration. This means that…

  20. LASIK - Laser Eye Surgery

    MedlinePLUS

    ... Uveitis Focus On Pediatric Ophthalmology Education Center Oculofacial Plastic Surgery Center Laser Surgery Education Center Redmond Ethics Center Global Ophthalmology Guide Academy Publications EyeNet Ophthalmology ...

  1. Amblyopia: Lazy Eye Symptoms

    MedlinePLUS

    ... Uveitis Focus On Pediatric Ophthalmology Education Center Oculofacial Plastic Surgery Center Laser Surgery Education Center Redmond Ethics Center Global Ophthalmology Guide Academy Publications EyeNet Ophthalmology ...

  2. Amblyopia: Lazy Eye Treatment

    MedlinePLUS

    ... Uveitis Focus On Pediatric Ophthalmology Education Center Oculofacial Plastic Surgery Center Laser Surgery Education Center Redmond Ethics Center Global Ophthalmology Guide Academy Publications EyeNet Ophthalmology ...

  3. Amblyopia: Lazy Eye Diagnosis

    MedlinePLUS

    ... Uveitis Focus On Pediatric Ophthalmology Education Center Oculofacial Plastic Surgery Center Laser Surgery Education Center Redmond Ethics Center Global Ophthalmology Guide Academy Publications EyeNet Ophthalmology ...

  4. Using Eye Makeup

    MedlinePLUS

    ... Uveitis Focus On Pediatric Ophthalmology Education Center Oculofacial Plastic Surgery Center Laser Surgery Education Center Redmond Ethics Center Global Ophthalmology Guide Academy Publications EyeNet Ophthalmology ...

  5. Eye Injuries at Work

    MedlinePLUS

    ... Uveitis Focus On Pediatric Ophthalmology Education Center Oculofacial Plastic Surgery Center Laser Surgery Education Center Redmond Ethics Center Global Ophthalmology Guide Academy Publications EyeNet Ophthalmology ...

  6. Preventing Eye Injuries

    MedlinePLUS

    ... Uveitis Focus On Pediatric Ophthalmology Education Center Oculofacial Plastic Surgery Center Laser Surgery Education Center Redmond Ethics Center Global Ophthalmology Guide Academy Publications EyeNet Ophthalmology ...

  7. Smoking and Eye Health

    MedlinePLUS

    ... Uveitis Focus On Pediatric Ophthalmology Education Center Oculofacial Plastic Surgery Center Laser Surgery Education Center Redmond Ethics Center Global Ophthalmology Guide Academy Publications EyeNet Ophthalmology ...

  8. Eye Injuries at Home

    MedlinePLUS

    ... Uveitis Focus On Pediatric Ophthalmology Education Center Oculofacial Plastic Surgery Center Laser Surgery Education Center Redmond Ethics Center Global Ophthalmology Guide Academy Publications EyeNet Ophthalmology ...

  9. The evolution of dominance.

    PubMed

    Bourguet, D

    1999-07-01

    The evolution of dominance has been subject to intensive debate since Fisher first argued that modifiers would be selected for if they made wild-type alleles more dominant over mutant alleles. An alternative explanation, put forward by Wright, is that the commonly observed dominance of wild-type alleles is simply a physiological consequence of metabolic pathways. Wright's explanation has gained support over the years, largely ending the debate over the general recessivity of deleterious mutations. Nevertheless there is reason to believe that dominance relationships have been moulded by natural selection to some extent. First, the metabolic pathways are themselves products of evolutionary processes that may have led them to be more stable to perturbations, including mutations. Secondly, theoretical models and empirical experiments suggest that substantial selection for dominance modifiers exists during the spread of adaptive alleles or when a polymorphism is maintained either by overdominant selection or by migration-selection balance. PMID:10447697

  10. [Dissociation of voluntary eye closure--to keep the eyes closed and to blink--following right hemisphere stroke].

    PubMed

    Wada, Y; Kita, Y; Yamamoto, T

    2000-06-01

    We report a case of a unique eye sign following right hemispheric infarction. This patient was a 78 year old right-handed woman. There was a history of a left hemispheric stroke 1 year previously. On admission, she showed left hemianopia, dysarthria, mild left central facial paresis, bilateral sensory deficit and quadriparesis which were marked on the left side. Babinski sign was elicited on the left. She did not have anosognosia or visual neglect. She had mild orofacial apraxia, but ideomotor and ideational apraxia was absent. There was no motor impersistence. Magnetic resonance imaging of the brain revealed a recent infarction in the territory of the right middle cerebral artery and an old infarction in the left tempro-parietal lobe. The patient could not open her eyelids to verbal command or voluntarily until about two weeks later, when she became able to open her eyes but showed difficulty keeping her left eye closed. She was aware of this problem and could repeat the command and comprehend what was requested to her. On verbal command to close the eyes, her right eye would be closed continuously and excessively and the left eye would only blink. When requested to blink, however, she could blink correctly without excessive eye closure. Spontaneous, reflex and voluntary blinking were normal. Her eyes were closed normally during sleep. Blepharospasm was not seen. The patient showed a striking dissociation between a failure to close her eyes continuously and a preserved ability to blink voluntarily. We suggest that her ability to contract palpebral portion of her left orbicularis oculi muscle is preserved. Regarding the mechanism of the voluntary eye closure system, separate control mechanisms should exist on closing eyes continuously and blinking. PMID:10875126

  11. Genotype-phenotype associations and human eye color.

    PubMed

    White, Désirée; Rabago-Smith, Montserrat

    2011-01-01

    Although eye color is usually modeled as a simple, Mendelian trait, further research and observation has indicated that eye color does not follow the classical paths of inheritance. Eye color phenotypes demonstrate both epistasis and incomplete dominance. Although there are about 16 different genes responsible for eye color, it is mostly attributed to two adjacent genes on chromosome 15, hect domain and RCC1-like domain-containing protein 2 (HERC2) and ocular albinism (that is, oculocutaneous albinism II (OCA2)). An intron in HERC2 contains the promoter region for OCA2, affecting its expression. Therefore, single-nucleotide polymorphisms in either of these two genes have a large role in the eye color of an individual. Furthermore, with all genetic expression, aberration also occurs. Some individuals may express two phenotypes--one in each eye--or a complete lack of pigmentation, ocular albinism. In addition, the evolutionary and population roles of the different expressions are significant. PMID:20944644

  12. Strand I: Physical Health. Sensory Perception. Health Curriculum Materials Grades 4, 5, 6.

    ERIC Educational Resources Information Center

    New York State Education Dept., Albany. Bureau of Elementary Curriculum Development.

    GRADES OR AGES: Grades 4, 5, and 6. SUBJECT MATTER: Sensory perceptions, the organs involved, and eye and hearing care. ORGANIZATION AND PHYSICAL APPEARANCE: The guide is divided into six different sectional steps organized around a gradual, ascending understanding of the sense organs. OBJECTIVES AND ACTIVITIES: The material is divided into…

  13. Sensory Changes in Later Life. A Pacific Northwest Extension Publication. PNW 196. Revised.

    ERIC Educational Resources Information Center

    Schmall, Vicki L.

    This booklet is designed to help persons who have elderly family members or who work with older adults understand and help compensate for the sensory changes that occur in later life. It contains sections on vision, hearing, taste and smell, and touch. Discussed in the section on vision are the following: common age-related changes, eye diseases…

  14. Feature-based attention in the frontal eye field and area V4 during visual search.

    PubMed

    Zhou, Huihui; Desimone, Robert

    2011-06-23

    When we search for a target in a crowded visual scene, we often use the distinguishing features of the target, such as color or shape, to guide our attention and eye movements. To investigate the neural mechanisms of feature-based attention, we simultaneously recorded neural responses in the frontal eye field (FEF) and area V4 while monkeys performed a visual search task. The responses of cells in both areas were modulated by feature attention, independent of spatial attention, and the magnitude of response enhancement was inversely correlated with the number of saccades needed to find the target. However, an analysis of the latency of sensory and attentional influences on responses suggested that V4 provides bottom-up sensory information about stimulus features, whereas the FEF provides a top-down attentional bias toward target features that modulates sensory processing in V4 and that could be used to guide the eyes to a searched-for target. PMID:21689605

  15. Modeling of the First Layers in the Fly's Eye

    NASA Technical Reports Server (NTRS)

    Moya, J. A.; Wilcox, M. J.; Donohoe, G. W.

    1997-01-01

    Increased autonomy of robots would yield significant advantages in the exploration of space. The shortfalls of computer vision can, however, pose significant limitations on a robot's potential. At the same time, simple insects which are largely hard-wired have effective visual systems. The understanding of insect vision systems thus may lead to improved approaches to visual tasks. A good starting point for the study of a vision system is its eye. In this paper, a model of the sensory portion of the fly's eye is presented. The effectiveness of the model is briefly addressed by a comparison of its performance to experimental data.

  16. Sex and Caste-Specific Variation in Compound Eye Morphology of Five Honeybee Species

    PubMed Central

    Streinzer, Martin; Brockmann, Axel; Nagaraja, Narayanappa; Spaethe, Johannes

    2013-01-01

    Ranging from dwarfs to giants, the species of honeybees show remarkable differences in body size that have placed evolutionary constrains on the size of sensory organs and the brain. Colonies comprise three adult phenotypes, drones and two female castes, the reproductive queen and sterile workers. The phenotypes differ with respect to tasks and thus selection pressures which additionally constrain the shape of sensory systems. In a first step to explore the variability and interaction between species size-limitations and sex and caste-specific selection pressures in sensory and neural structures in honeybees, we compared eye size, ommatidia number and distribution of facet lens diameters in drones, queens and workers of five species (Apis andreniformis, A. florea, A. dorsata, A. mellifera, A. cerana). In these species, male and female eyes show a consistent sex-specific organization with respect to eye size and regional specialization of facet diameters. Drones possess distinctly enlarged eyes with large dorsal facets. Aside from these general patterns, we found signs of unique adaptations in eyes of A. florea and A. dorsata drones. In both species, drone eyes are disproportionately enlarged. In A. dorsata the increased eye size results from enlarged facets, a likely adaptation to crepuscular mating flights. In contrast, the relative enlargement of A. florea drone eyes results from an increase in ommatidia number, suggesting strong selection for high spatial resolution. Comparison of eye morphology and published mating flight times indicates a correlation between overall light sensitivity and species-specific mating flight times. The correlation suggests an important role of ambient light intensities in the regulation of species-specific mating flight times and the evolution of the visual system. Our study further deepens insights into visual adaptations within the genus Apis and opens up future perspectives for research to better understand the timing mechanisms and sensory physiology of mating related signals. PMID:23460896

  17. Sex and caste-specific variation in compound eye morphology of five honeybee species.

    PubMed

    Streinzer, Martin; Brockmann, Axel; Nagaraja, Narayanappa; Spaethe, Johannes

    2013-01-01

    Ranging from dwarfs to giants, the species of honeybees show remarkable differences in body size that have placed evolutionary constrains on the size of sensory organs and the brain. Colonies comprise three adult phenotypes, drones and two female castes, the reproductive queen and sterile workers. The phenotypes differ with respect to tasks and thus selection pressures which additionally constrain the shape of sensory systems. In a first step to explore the variability and interaction between species size-limitations and sex and caste-specific selection pressures in sensory and neural structures in honeybees, we compared eye size, ommatidia number and distribution of facet lens diameters in drones, queens and workers of five species (Apis andreniformis, A. florea, A. dorsata, A. mellifera, A. cerana). In these species, male and female eyes show a consistent sex-specific organization with respect to eye size and regional specialization of facet diameters. Drones possess distinctly enlarged eyes with large dorsal facets. Aside from these general patterns, we found signs of unique adaptations in eyes of A. florea and A. dorsata drones. In both species, drone eyes are disproportionately enlarged. In A. dorsata the increased eye size results from enlarged facets, a likely adaptation to crepuscular mating flights. In contrast, the relative enlargement of A. florea drone eyes results from an increase in ommatidia number, suggesting strong selection for high spatial resolution. Comparison of eye morphology and published mating flight times indicates a correlation between overall light sensitivity and species-specific mating flight times. The correlation suggests an important role of ambient light intensities in the regulation of species-specific mating flight times and the evolution of the visual system. Our study further deepens insights into visual adaptations within the genus Apis and opens up future perspectives for research to better understand the timing mechanisms and sensory physiology of mating related signals. PMID:23460896

  18. Navigation Using Sensory Substitution in Real and Virtual Mazes

    PubMed Central

    Chebat, Daniel-Robert; Maidenbaum, Shachar; Amedi, Amir

    2015-01-01

    Under certain specific conditions people who are blind have a perception of space that is equivalent to that of sighted individuals. However, in most cases their spatial perception is impaired. Is this simply due to their current lack of access to visual information or does the lack of visual information throughout development prevent the proper integration of the neural systems underlying spatial cognition? Sensory Substitution devices (SSDs) can transfer visual information via other senses and provide a unique tool to examine this question. We hypothesize that the use of our SSD (The EyeCane: a device that translates distance information into sounds and vibrations) can enable blind people to attain a similar performance level as the sighted in a spatial navigation task. We gave fifty-six participants training with the EyeCane. They navigated in real life-size mazes using the EyeCane SSD and in virtual renditions of the same mazes using a virtual-EyeCane. The participants were divided into four groups according to visual experience: congenitally blind, low vision & late blind, blindfolded sighted and sighted visual controls. We found that with the EyeCane participants made fewer errors in the maze, had fewer collisions, and completed the maze in less time on the last session compared to the first. By the third session, participants improved to the point where individual trials were no longer significantly different from the initial performance of the sighted visual group in terms of errors, time and collision. PMID:26039580

  19. Sensory adaptation for timing perception

    PubMed Central

    Roseboom, Warrick; Linares, Daniel; Nishida, Shin'ya

    2015-01-01

    Recent sensory experience modifies subjective timing perception. For example, when visual events repeatedly lead auditory events, such as when the sound and video tracks of a movie are out of sync, subsequent vision-leads-audio presentations are reported as more simultaneous. This phenomenon could provide insights into the fundamental problem of how timing is represented in the brain, but the underlying mechanisms are poorly understood. Here, we show that the effect of recent experience on timing perception is not just subjective; recent sensory experience also modifies relative timing discrimination. This result indicates that recent sensory history alters the encoding of relative timing in sensory areas, excluding explanations of the subjective phenomenon based only on decision-level changes. The pattern of changes in timing discrimination suggests the existence of two sensory components, similar to those previously reported for visual spatial attributes: a lateral shift in the nonlinear transducer that maps relative timing into perceptual relative timing and an increase in transducer slope around the exposed timing. The existence of these components would suggest that previous explanations of how recent experience may change the sensory encoding of timing, such as changes in sensory latencies or simple implementations of neural population codes, cannot account for the effect of sensory adaptation on timing perception. PMID:25788590

  20. Sensory adaptation for timing perception.

    PubMed

    Roseboom, Warrick; Linares, Daniel; Nishida, Shin'ya

    2015-04-22

    Recent sensory experience modifies subjective timing perception. For example, when visual events repeatedly lead auditory events, such as when the sound and video tracks of a movie are out of sync, subsequent vision-leads-audio presentations are reported as more simultaneous. This phenomenon could provide insights into the fundamental problem of how timing is represented in the brain, but the underlying mechanisms are poorly understood. Here, we show that the effect of recent experience on timing perception is not just subjective; recent sensory experience also modifies relative timing discrimination. This result indicates that recent sensory history alters the encoding of relative timing in sensory areas, excluding explanations of the subjective phenomenon based only on decision-level changes. The pattern of changes in timing discrimination suggests the existence of two sensory components, similar to those previously reported for visual spatial attributes: a lateral shift in the nonlinear transducer that maps relative timing into perceptual relative timing and an increase in transducer slope around the exposed timing. The existence of these components would suggest that previous explanations of how recent experience may change the sensory encoding of timing, such as changes in sensory latencies or simple implementations of neural population codes, cannot account for the effect of sensory adaptation on timing perception. PMID:25788590

  1. Sensory gating, cannabinoids and schizophrenia.

    PubMed

    Dissanayake, Dilshani W N; Mason, Robert; Marsden, Charles A

    2013-04-01

    Sensory gating, a mandatory process in early information processing, has been found to be defective in neuropsychiatric diseases such as schizophrenia. Understanding the neurobiology of sensory gating may provide insight into unravelling the neurobiology of information processing and to yet unanswered queries on the pathophysiology of disabling neuropsychiatric diseases. The endocannabinoid system has been linked to the pathophysiology of schizophrenia. Furthermore, cannabinoids disrupt sensory gating in animals and humans which supports the hypothesis that the disruption of sensory gating by alterations in the endocannabinoid system is a significant factor in the etiology of schizophrenia. Based on the above hypothesis this article reviews the sensory gating process in relation to the auditory conditioning-test paradigm with an emphasis on its association with the endocannabinoid system and schizophrenia. PMID:23154301

  2. Sensory aspects of movement disorders

    PubMed Central

    Patel, Neepa; Jankovic, Joseph; Hallett, Mark

    2016-01-01

    Movement disorders, which include disorders such as Parkinson’s disease, dystonia, Tourette’s syndrome, restless legs syndrome, and akathisia, have traditionally been considered to be disorders of impaired motor control resulting predominantly from dysfunction of the basal ganglia. This notion has been revised largely because of increasing recognition of associated behavioural, psychiatric, autonomic, and other non-motor symptoms. The sensory aspects of movement disorders include intrinsic sensory abnormalities and the effects of external sensory input on the underlying motor abnormality. The basal ganglia, cerebellum, thalamus, and their connections, coupled with altered sensory input, seem to play a key part in abnormal sensorimotor integration. However, more investigation into the phenomenology and physiological basis of sensory abnormalities, and about the role of the basal ganglia, cerebellum, and related structures in somatosensory processing, and its effect on motor control, is needed. PMID:24331796

  3. Sensory analysis of pet foods.

    PubMed

    Koppel, Kadri

    2014-08-01

    Pet food palatability depends first and foremost on the pet and is related to the pet food sensory properties such as aroma, texture and flavor. Sensory analysis of pet foods may be conducted by humans via descriptive or hedonic analysis, pets via acceptance or preference tests, and through a number of instrumental analysis methods. Sensory analysis of pet foods provides additional information on reasons behind palatable and unpalatable foods as pets lack linguistic capabilities. Furthermore, sensory analysis may be combined with other types of information such as personality and environment factors to increase understanding of acceptable pet foods. Most pet food flavor research is proprietary and, thus, there are a limited number of publications available. Funding opportunities for pet food studies would increase research and publications and this would help raise public awareness of pet food related issues. This mini-review addresses current pet food sensory analysis literature and discusses future challenges and possibilities. PMID:24497160

  4. Autologous serum eye drops for dry eye

    PubMed Central

    Pan, Qing; Angelina, Adla; Zambrano, Andrea; Marrone, Michael; Stark, Walter J; Heflin, Thomas; Tang, Li; Akpek, Esen K

    2014-01-01

    Background Theoretically, autologous serum eye drops (AS) have a potential advantage over traditional therapies based on the assumption that AS serve not only as a lacrimal substitute to provide lubrication, but also contain other biochemical components mimicking natural tears more closely. The application of AS in dry eye treatment has gained popularity as a second-line therapy in the treatment of dry eye. Published studies on the subject indicate that autologous serum could be an effective treatment for dry eye. Objectives To evaluate the efficacy and safety of AS compared to artificial tears for treating dry eye. Search methods We searched CENTRAL (which contains the Cochrane Eyes and Vision Group Trials Register) (The Cochrane Library 2013, Issue 3), Ovid MEDLINE, Ovid MEDLINE In-Process and Other Non-Indexed Citations, Ovid MEDLINE Daily, Ovid OLD MEDLINE, (January 1950 to April 2013), EMBASE (January 1980 to April 2013), Latin American and Caribbean Literature on Health Sciences (LILACS) (January 1982 to April 2013), the meta Register of Controlled Trials (mRCT) (www.controlled-trials.com), ClinicalTrials.gov (www.clinicaltrials.gov) and the WHO International Clinical Trials Registry Platform (ICTRP) (www.who.int/ictrp/search/en). We also searched the Science Citation Index Expanded database (September 2013) and reference lists of included studies. We did not use any date or language restrictions in the electronic searches for trials. We last searched the electronic databases on 15 April 2013. Selection criteria We included randomized controlled trials (RCTs) in which AS was compared to artificial tears in the treatment of dry eye in adults. Data collection and analysis Two review authors independently screened all titles and abstracts and assessed full-text articles of potentially eligible trials. Two review authors extracted data and assessed the methodological quality and characteristics of the included trials.We contacted investigators for missing data. For both primary and secondary outcomes, we reported mean differences with corresponding 95% confidence intervals (CIs) for continuous outcomes. Main results We identified four eligible RCTs in which AS was compared with artificial tear treatment or saline in individuals (n = 72 participants) with dry eye of various etiologies (Sjögren’s syndrome-related dry eye, non-Sjögren’s syndrome dry eye and postoperative dry eye induced by laser-assisted in situ keratomileusis (LASIK)). The quality of the evidence provided by these trials was variable. A majority of the risk of bias domains were judged to have an unclear risk of bias in two trials owing to insufficient reporting of trial characteristics. One trial was considered to have a low risk of bias for most domains while another was considered to have a high risk of bias for most domains. Incomplete outcome reporting and heterogeneity in the participant populations and follow-up periods prevented the inclusion of these trials in a summary meta-analysis. For the primary outcome, improvement in participant-reported symptoms at one month, one trial (12 participants) showed no difference in participant-reported symptoms between 20% AS and artificial tears. Based on the results of two trials in 32 participants, 20% AS may provide some improvement in participant-reported symptoms compared to traditional artificial tears after two weeks of treatment. One trial also showed positive results with a mean difference in tear breakup time (TBUT) of 2.00 seconds (95% CI 0.99 to 3.01 seconds) between 20% AS and artificial tears after two weeks, which were not similar to findings from the other trials. Based on all other objective clinical assessments included in this review, AS was not associated with improvements in aqueous tear production measured by Schirmer’s test (two trials, 33 participants), ocular surface condition with fluorescein (four trials, 72 participants) or Rose Bengal staining (three trials, 60 participants), and epithelial metaplasia by impression cytology compared to artificial tea

  5. Photorefraction of the Eye

    ERIC Educational Resources Information Center

    Colicchia, Giuseppe; Wiesner, Hartmut; Zollman, Dean

    2015-01-01

    Photorefraction is a method to easily estimate the refractive state of the eye. The principle of photorefraction involves projecting light into the eye during flash photography and then examining the paths of light that emerge from the pupil after scattering on the back portion of the interior of the eyeball (fundus). We will explain the optical…

  6. An Eye for Learning.

    ERIC Educational Resources Information Center

    Ostwald, Thomas

    1995-01-01

    Presents a hands-on activity as an excellent starting point for investigations related to the eye. Involves making a simple model of the vertebrate eye to illustrate the formation of an upside-down image on the retina by the lens. Links to investigations in numerous science disciplines including astronomy, genetics, biology, earth science, and…

  7. Photorefraction of the Eye

    ERIC Educational Resources Information Center

    Colicchia, Giuseppe; Wiesner, Hartmut; Zollman, Dean

    2015-01-01

    Photorefraction is a method to easily estimate the refractive state of the eye. The principle of photorefraction involves projecting light into the eye during flash photography and then examining the paths of light that emerge from the pupil after scattering on the back portion of the interior of the eyeball (fundus). We will explain the optical…

  8. Excitatory Synaptic Feedback from the Motor Layer to the Sensory Layers of the Superior Colliculus

    PubMed Central

    Ghitani, Nima; Bayguinov, Peter O.; Vokoun, Corinne R.; McMahon, Shane

    2014-01-01

    Neural circuits that translate sensory information into motor commands are organized in a feedforward manner converting sensory information into motor output. The superior colliculus (SC) follows this pattern as it plays a role in converting visual information from the retina and visual cortex into motor commands for rapid eye movements (saccades). Feedback from movement to sensory regions is hypothesized to play critical roles in attention, visual image stability, and saccadic suppression, but in contrast to feedforward pathways, motor feedback to sensory regions has received much less attention. The present study used voltage imaging and patch-clamp recording in slices of rat SC to test the hypothesis of an excitatory synaptic pathway from the motor layers of the SC back to the sensory superficial layers. Voltage imaging revealed an extensive depolarization of the superficial layers evoked by electrical stimulation of the motor layers. A pharmacologically isolated excitatory synaptic potential in the superficial layers depended on stimulus strength in the motor layers in a manner consistent with orthodromic excitation. Patch-clamp recording from neurons in the sensory layers revealed excitatory synaptic potentials in response to glutamate application in the motor layers. The location, size, and morphology of responsive neurons indicated they were likely to be narrow-field vertical cells. This excitatory projection from motor to sensory layers adds an important element to the circuitry of the SC and reveals a novel feedback pathway that could play a role in enhancing sensory responses to attended targets as well as visual image stabilization. PMID:24828636

  9. Autosomal dominant genes (image)

    MedlinePLUS

    ... case of autosomal dominant genes, a single abnormal gene on one of the autosomal chromosomes (one of the first 22 "non-sex" chromosomes) from either parent can cause the disease. One of the parents ...

  10. Eye burning - itching and discharge

    MedlinePLUS

    ... allergies or hay fever Infections, bacterial or viral ( conjunctivitis or pink eye) Chemical irritants (such as chlorine ... to help with allergies. Pink eye or viral conjunctivitis causes a red or bloodshot eye and excessive ...

  11. Multistability in perception: binding sensory modalities, an overview.

    PubMed

    Schwartz, Jean-Luc; Grimault, Nicolas; Hupé, Jean-Michel; Moore, Brian C J; Pressnitzer, Daniel

    2012-04-01

    This special issue presents research concerning multistable perception in different sensory modalities. Multistability occurs when a single physical stimulus produces alternations between different subjective percepts. Multistability was first described for vision, where it occurs, for example, when different stimuli are presented to the two eyes or for certain ambiguous figures. It has since been described for other sensory modalities, including audition, touch and olfaction. The key features of multistability are: (i) stimuli have more than one plausible perceptual organization; (ii) these organizations are not compatible with each other. We argue here that most if not all cases of multistability are based on competition in selecting and binding stimulus information. Binding refers to the process whereby the different attributes of objects in the environment, as represented in the sensory array, are bound together within our perceptual systems, to provide a coherent interpretation of the world around us. We argue that multistability can be used as a method for studying binding processes within and across sensory modalities. We emphasize this theme while presenting an outline of the papers in this issue. We end with some thoughts about open directions and avenues for further research. PMID:22371612

  12. Multistability in perception: binding sensory modalities, an overview

    PubMed Central

    Schwartz, Jean-Luc; Grimault, Nicolas; Hupé, Jean-Michel; Moore, Brian C. J.; Pressnitzer, Daniel

    2012-01-01

    This special issue presents research concerning multistable perception in different sensory modalities. Multistability occurs when a single physical stimulus produces alternations between different subjective percepts. Multistability was first described for vision, where it occurs, for example, when different stimuli are presented to the two eyes or for certain ambiguous figures. It has since been described for other sensory modalities, including audition, touch and olfaction. The key features of multistability are: (i) stimuli have more than one plausible perceptual organization; (ii) these organizations are not compatible with each other. We argue here that most if not all cases of multistability are based on competition in selecting and binding stimulus information. Binding refers to the process whereby the different attributes of objects in the environment, as represented in the sensory array, are bound together within our perceptual systems, to provide a coherent interpretation of the world around us. We argue that multistability can be used as a method for studying binding processes within and across sensory modalities. We emphasize this theme while presenting an outline of the papers in this issue. We end with some thoughts about open directions and avenues for further research. PMID:22371612

  13. Achromatizing the human eye.

    PubMed

    Bradley, A; Zhang, X X; Thibos, L N

    1991-08-01

    Ocular chromatic dispersion manifests itself as wavelength-dependent image planes, image sizes, and image positions, and it has been suggested that ocular chromatic aberration is the most important of the eye's optical aberrations. Most attempts to correct for the eye's chromatic aberration (achromatize the human eye) have concentrated on correcting the wavelength-dependent image planes or chromatic difference of refractive error (CDRx). There are two optical techniques that correct for CDRx (special achromatizing lenses and multiple channel display systems) by making the ocular image planes of all wavelengths coincident. A different approach simply avoids the effects of ocular CDRx by using small pupils which effectively make all images diffraction-limited irrespective of wavelength-dependent differences in image planes. Theoretical and experimental evidence shows that achromatizing lenses provide an accurate correction for CDRx. In spite of the pre-eminence of chromatic aberrations, and the effectiveness of the corrections, no obvious improvements in vision accompany correction. We show that loss of retinal image quality due to CDRx may be subthreshold (less than ocular depth of focus). We also show that achromatizing methods can introduce their own chromatic aberrations that can easily exceed those present in the uncorrected eye. The precise location of the eye with respect to the achromatizing device determines the amount of these additional aberrations. Therefore, in order to achromatize the eye effectively, careful control of eye position is essential. PMID:1923337

  14. Advocacy for eye care

    PubMed Central

    Ravilla, Thulasiraj D; Ramasamy, Dhivya

    2012-01-01

    The effectiveness of eye care service delivery is often dependant on how the different stakeholders are aligned. These stakeholders range from the ministries of health who have the capacity to grant government subsidies for eye care, down to the primary healthcare workers who can be enrolled to screen for basic eye diseases. Advocacy is a tool that can help service providers draw the attention of key stakeholders to a particular area of concern. By enlisting the support, endorsement and participation of a wider circle of players, advocacy can help to improve the penetration and effectiveness of the services provided. There are several factors in the external environmental that influence the eye care services – such as the availability of trained manpower, supply of eye care consumables, government rules and regulations. There are several instances where successful advocacy has helped to create an enabling environment for eye care service delivery. Providing eye care services in developing countries requires the support – either for direct patient care or for support services such as producing trained manpower or for research and dissemination. Such support, in the form of financial or other resources, can be garnered through advocacy. PMID:22944745

  15. Painful channels in sensory neurons.

    PubMed

    Lee, Yunjong; Lee, Chang-Hun; Oh, Uhtaek

    2005-12-31

    Pain is an unpleasant sensation experienced when tissues are damaged. Thus, pain sensation in some way protects body from imminent threat or injury. Peripheral sensory nerves innervated to peripheral tissues initially respond to multiple forms of noxious or strong stimuli, such as heat, mechanical and chemical stimuli. In response to these stimuli, electrical signals for conducting the nociceptive neural signals through axons are generated. These action potentials are then conveyed to specific areas in the spinal cord and in the brain. Sensory afferent fibers are heterogeneous in many aspects. For example, sensory nerves are classified as Aa, -b, -d and C-fibers according to their diameter and degree of myelination. It is widely accepted that small sensory fibers tend to respond to vigorous or noxious stimuli and related to nociception. Thus these fibers are specifically called nociceptors. Most of nociceptors respond to noxious mechanical stimuli and heat. In addition, these sensory fibers also respond to chemical stimuli [Davis et al. (1993)] such as capsaicin. Thus, nociceptors are considered polymodal. Recent advance in research on ion channels in sensory neurons reveals molecular mechanisms underlying how various types of stimuli can be transduced to neural signals transmitted to the brain for pain perception. In particular, electrophysiological studies on ion channels characterize biophysical properties of ion channels in sensory neurons. Furthermore, molecular biology leads to identification of genetic structures as well as molecular properties of ion channels in sensory neurons. These ion channels are expressed in axon terminals as well as in cell soma. When these channels are activated, inward currents or outward currents are generated, which will lead to depolarization or hyperpolarization of the membrane causing increased or decreased excitability of sensory neurons. In order to depolarize the membrane of nerve terminals, either inward currents should be generated or outward currents should be inhibited. So far, many cationic channels that are responsible for the excitation of sensory neurons are introduced recently. Activation of these channels in sensory neurons is evidently critical to the generation of nociceptive signals. The main channels responsible for inward membrane currents in nociceptors are voltage-activated sodium and calcium channels, while outward current is carried mainly by potassium ions. In addition, activation of non-selective cation channels is also responsible for the excitation of sensory neurons. Thus, excitability of neurons can be controlled by regulating expression or by modulating activity of these channels. PMID:16404144

  16. Eye-Safe Lidar

    NASA Technical Reports Server (NTRS)

    Byer, Robert L.

    1989-01-01

    Laser infrared radar (lidar) undergoing development harmless to human eyes, consists almost entirely of solid-state components, and offers high range resolution. Operates at wavelength of about 2 micrometers. If radiation from such device strikes eye, almost completely absorbed by cornea without causing damage, even if aimed directly at eye. Continuous-wave light from laser oscillator amplified and modulated for transmission from telescope. Small portion of output of oscillator fed to single-mode fiber coupler, where mixed with return pulses. Intended for remote Doppler measurements of winds and differential-absorption measurements of concentrations of gases in atmosphere.

  17. Physiological Targets of Artificial Gravity: The Sensory-Motor System. Chapter 4

    NASA Technical Reports Server (NTRS)

    Paloski, William; Groen, Eric; Clarke, Andrew; Bles, Willem; Wuyts, Floris; Paloski, William; Clement, Gilles

    2006-01-01

    This chapter describes the pros and cons of artificial gravity applications in relation to human sensory-motor functioning in space. Spaceflight creates a challenge for sensory-motor functions that depend on gravity, which include postural balance, locomotion, eye-hand coordination, and spatial orientation. The sensory systems, and in particular the vestibular system, must adapt to weightlessness on entering orbit, and again to normal gravity upon return to Earth. During this period of adaptation, which persists beyond the actual gravity-level transition itself the sensory-motor systems are disturbed. Although artificial gravity may prove to be beneficial for the musculoskeletal and cardiovascular systems, it may well have negative side effects for the neurovestibular system, such as spatial disorientation, malcoordination, and nausea.

  18. Autosomal dominant vitreoretinochoroidopathy (ADVIRC).

    PubMed Central

    Blair, N P; Goldberg, M F; Fishman, G A; Salzano, T

    1984-01-01

    We report the second family recognised to have autosomal dominant vitreoretinochoroidopathy. The clinical features were (1) autosomal dominant inheritance; (2) peripheral, coarse pigmentary degeneration of the fundus for 360 degrees, with a relatively discrete posterior border in the equatorial region (this finding may be pathognomonic); (3) superficial punctate yellowish-white opacities in the retina; (4) various vascular abnormalities; (5) breakdown of the blood-retinal barrier; (6) retinal neovascularisation; (7) vitreous abnormalities; and (8) choroidal atrophy. Visual reduction was mainly due to macular oedema or vitreous haemorrhage. Images PMID:6689931

  19. Language after dominant hemispherectomy

    PubMed Central

    Gott, Piggy S.

    1973-01-01

    Linguistic and related cognitive abilities were investigated two years after dominant left hemispherectomy for cerebral malignancy in a 12 year old female. Auditory comprehension of speech was superior to other modes of language abilities with expressive speech being the least developed. Findings suggested an isolation or non-communication between the systems for speaking and for writing and visual perception. It was concluded that language mechanisms in the right hemisphere were not just at a low level of development of the functions found in the dominant hemisphere but were modified as a result of interference by preexistent spatioperceptual systems. Images PMID:4772723

  20. What Is Eye Cancer?

    MedlinePLUS

    ... of cancers, see our documents on them. Intraocular melanoma (melanoma of the eye) Intraocular melanoma is the most ... the rest of this document focuses on intraocular melanomas and lymphomas. Last Medical Review: 12/09/2014 ...

  1. Why Do Eyes Water?

    MedlinePLUS

    ... water, they're making tears, just like when you cry. The tears from watering eyes help protect your ... ever noticed that your nose sometimes runs when you cry? That's because some of the tears making their ...

  2. Eye Drop Tips

    MedlinePLUS

    ... to the disease. Read more » Alternative Medicine Eye Drop Tips Financial Assistance Find a Doctor Glaucoma Surgery Living With Glaucoma Low Vision Resources Medication Guide Resources on the Web » See All Articles Help the Cause Glaucoma affects ...

  3. Dry eye syndrome

    MedlinePLUS

    ... of dry eyes include: Dry environment or workplace (wind, air conditioning) Sun exposure Smoking or second-hand ... NOT smoke and avoid second-hand smoke, direct wind, and air conditioning. Use a humidifier, especially in ...

  4. Diabetic Eye Problems

    MedlinePLUS

    ... damage your eyes. The most common problem is diabetic retinopathy. It is a leading cause of blindness ... You need a healthy retina to see clearly. Diabetic retinopathy damages the tiny blood vessels inside your ...

  5. Eye Cosmetic Safety

    MedlinePLUS

    ... from the applicator, and use of unapproved color additives. Keep it clean! Eye cosmetics are usually safe ... In the United States, the use of color additives is strictly regulated. A number of color additives ...

  6. Eye Injuries (For Parents)

    MedlinePLUS

    ... the eyelid. Others, like those that happen during sports activities, can be serious and require medical attention. Signs and Symptoms redness stinging or burning watering sensitivity to light blurred vision swelling of the eyelids discoloration around the eye ...

  7. Lasik eye surgery - discharge

    MedlinePLUS

    Laser-assisted in situ keratomileusis - discharge; Laser vision correction - discharge; LASIK - discharge ... after surgery: Swimming Hot tubs and whirlpool Contact sports Lotions and creams Eye makeup The doctor will ...

  8. Multimodal eye recognition

    NASA Astrophysics Data System (ADS)

    Zhou, Zhi; Du, Yingzi; Thomas, N. L.; Delp, Edward J., III

    2010-04-01

    Multimodal biometrics use more than one means of biometric identification to achieve higher recognition accuracy, since sometimes a unimodal biometric is not good enough used to do identification and classification. In this paper, we proposed a multimodal eye recognition system, which can obtain both iris and sclera patterns from one color eye image. Gabor filter and 1-D Log-Gabor filter algorithms have been applied as the iris recognition algorithms. In sclera recognition, we introduced automatic sclera segmentation, sclera pattern enhancement, sclera pattern template generation, and sclera pattern matching. We applied kernelbased matching score fusion to improve the performance of the eye recognition system. The experimental results show that the proposed eye recognition method can achieve better performance compared to unimodal biometric identification, and the accuracy of our proposed kernel-based matching score fusion method is higher than two classic linear matching score fusion methods: Principal Component Analysis (PCA) and Linear Discriminant Analysis (LDA).

  9. Eye Injuries in Sports

    MedlinePLUS

    ... these injuries can be prevented. Overall, basketball and baseball cause the most eye injuries, followed by water ... involve body contact. Some high-risk sports are baseball, basketball, hockey, football, lacrosse, tennis and other racquet ...

  10. Diabetes and eye disease

    MedlinePLUS

    ... brain. Diabetic retinopathy is a main cause of blindness in Americans 20 to 74 years old. People ... pressure in the eye that can lead to blindness Macular edema -- blurry vision due to fluid leaking ...

  11. Iron dominated magnets

    SciTech Connect

    Fischer, G.E.

    1985-07-01

    These two lectures on iron dominated magnets are meant for the student of accelerator science and contain general treatments of the subjects design and construction. The material is arranged in the categories: General Concepts and Cost Considerations, Profile Configuration and Harmonics, Magnetic Measurements, a few examples of ''special magnets'' and Materials and Practices. Extensive literature is provided.

  12. Proceedings: Debilitating Eye Diseases

    PubMed Central

    Littman, Neil; Abo, Arie

    2014-01-01

    SUMMARY Debilitating eye diseases such as age-related macular degeneration and retinitis pigmentosa currently represent a large unmet medical need that could potentially be addressed by stem cell therapy. A number of novel stem cell-based cellular therapies are now under development to treat a variety of eye diseases. The approaches being taken by the California Institute for Regenerative Medicine, together with its grantees, are discussed. PMID:25378652

  13. [Straight in the eyes].

    PubMed

    Diop, E; Beylot, V; Berta, C; Dugardin, C; Aigle, L

    2015-01-01

    This case report about a young French soldier hit in the eye by a spitting cobra in the Central African Republic prompts us to review the potential toxicity of this venom to the eyes and the management of this injury. The initial phase is simple to implement, but is often performed badly or not at all because unknown. It is a condition, however, for optimal recovery of the cornea. PMID:26067984

  14. Modern sports eye injuries

    PubMed Central

    Capão Filipe, J A; Rocha-Sousa, A; Falcão-Reis, F; Castro-Correia, J

    2003-01-01

    Aims: To determine the severity and long term sequelae of eye injuries caused by modern sports that could be responsible for significant ocular trauma in the future. Methods: Prospective observational study of 24 (25 eyes) athletes with sports related ocular injuries from health clubs, war games, adventure, radical and new types of soccer, presenting to an eye emergency department between 1992 and 2002 (10 years). Results: Modern sports were responsible for 8.3% of the 288 total sports eye injuries reported. Squash (29.2%) was the most common cause, followed by paintball (20.8%) and motocross (16.6%). The most common diagnosis during the follow up period was retinal breaks (20%). 18 (75%) patients sustained a severe injury. The final visual acuity remained <20/100 in two paintball players. Conclusions: Ocular injuries resulting from modern sports are often severe. Adequate instruction of the participants in the games, proper use of eye protectors, and a routine complete ophthalmological examination after an eye trauma should be mandatory. PMID:14609827

  15. Trait Dominance Promotes Reflexive Staring at Masked Angry Body Postures

    PubMed Central

    Hortensius, Ruud; van Honk, Jack; de Gelder, Beatrice; Terburg, David

    2014-01-01

    It has been shown that dominant individuals sustain eye-contact when non-consciously confronted with angry faces, suggesting reflexive mechanisms underlying dominance behaviors. However, dominance and submission can be conveyed and provoked by means of not only facial but also bodily features. So far few studies have investigated the interplay of body postures with personality traits and behavior, despite the biological relevance and ecological validity of these postures. Here we investigate whether non-conscious exposure to bodily expressions of anger evokes reflex-like dominance behavior. In an interactive eye-tracking experiment thirty-two participants completed three social dominance tasks with angry, happy and neutral facial, bodily and face and body compound expressions that were masked from consciousness. We confirmed our predictions of slower gaze-aversion from both non-conscious bodily and compound expressions of anger compared to happiness in high dominant individuals. Results from a follow-up experiment suggest that the dominance behavior triggered by exposure to bodily anger occurs with basic detection of the category, but not recognition of the emotional content. Together these results suggest that dominant staring behavior is reflexively driven by non-conscious perception of the emotional content and triggered by not only facial but also bodily expression of anger. PMID:25549321

  16. Eye donation movement in India.

    PubMed

    Kannan, K A

    1999-08-01

    Late Dr RES Muthiah started the very first eye bank in India and the first corneal transplantation took place successfully by him in India in 1948. From then on a movement started for donation of eyes. The prime concept of Eye Bank Association of India (EBAI) is to motivate the people for eye donation. A vast propaganda throughout the country is going on for eye donation. The community should come forward shedding all inhibitions. EBAI has envisaged a master plan of action to regulate eye bank activities. Under this plan eye donation movement is catching up in the country. PMID:10643183

  17. Different topological organization of human brain functional networks with eyes open versus eyes closed.

    PubMed

    Xu, Pengfei; Huang, Ruiwang; Wang, Jinhui; Van Dam, Nicholas T; Xie, Teng; Dong, Zhangye; Chen, Chunping; Gu, Ruolei; Zang, Yu-Feng; He, Yong; Fan, Jin; Luo, Yue-jia

    2014-04-15

    Opening and closing the eyes are fundamental behaviors for directing attention to the external versus internal world. However, it remains unclear whether the states of eyes-open (EO) relative to eyes-closed (EC) are associated with different topological organizations of functional neural networks for exteroceptive and interoceptive processing (processing the external world and internal state, respectively). Here, we used resting-state functional magnetic resonance imaging and neural network analysis to investigate the topological properties of functional networks of the human brain when the eyes were open versus closed. The brain networks exhibited higher cliquishness and local efficiency, but lower global efficiency during the EO state compared to the EC state. These properties suggest an increase in specialized information processing along with a decrease in integrated information processing in EO (vs. EC). More importantly, the "exteroceptive" network, including the attentional system (e.g., superior parietal gyrus and inferior parietal lobule), ocular motor system (e.g., precentral gyrus and superior frontal gyrus), and arousal system (e.g., insula and thalamus), showed higher regional nodal properties (nodal degree, efficiency and betweenness centrality) in EO relative to EC. In contrast, the "interoceptive" network, composed of visual system (e.g., lingual gyrus, fusiform gyrus and cuneus), auditory system (e.g., Heschl's gyurs), somatosensory system (e.g., postcentral gyrus), and part of the default mode network (e.g., angular gyrus and anterior cingulate gyrus), showed significantly higher regional properties in EC vs. EO. In addition, the connections across sensory modalities were altered by volitional eye opening. The synchronicity between the visual system and the motor, somatosensory and auditory systems, characteristic of EC, was attenuated in EO. Further, the connections between the visual system and the attention, arousal and subcortical systems were increased in EO. These results may indicate that EO leads to a suppression of sensory modalities (other than visual) to allocate resources to exteroceptive processing. Our findings suggest that the topological organization of human brain networks dynamically switches corresponding to the information processing modes as we open or close our eyes. PMID:24434242

  18. Integration of Sensory and Reward Information during Perceptual Decision-Making in Lateral Intraparietal Cortex (LIP) of the Macaque Monkey

    PubMed Central

    Rorie, Alan E.; Gao, Juan; McClelland, James L.; Newsome, William T.

    2010-01-01

    Single neurons in cortical area LIP are known to carry information relevant to both sensory and value-based decisions that are reported by eye movements. It is not known, however, how sensory and value information are combined in LIP when individual decisions must be based on a combination of these variables. To investigate this issue, we conducted behavioral and electrophysiological experiments in rhesus monkeys during performance of a two-alternative, forced-choice discrimination of motion direction (sensory component). Monkeys reported each decision by making an eye movement to one of two visual targets associated with the two possible directions of motion. We introduced choice biases to the monkeys' decision process (value component) by randomly interleaving balanced reward conditions (equal reward value for the two choices) with unbalanced conditions (one alternative worth twice as much as the other). The monkeys' behavior, as well as that of most LIP neurons, reflected the influence of all relevant variables: the strength of the sensory information, the value of the target in the neuron's response field, and the value of the target outside the response field. Overall, detailed analysis and computer simulation reveal that our data are consistent with a two-stage drift diffusion model proposed by Diederich and Bussmeyer [1] for the effect of payoffs in the context of sensory discrimination tasks. Initial processing of payoff information strongly influences the starting point for the accumulation of sensory evidence, while exerting little if any effect on the rate of accumulation of sensory evidence. PMID:20174574

  19. Sural and Radial Sensory Responses in Patients with Sensory Polyneuropathy

    PubMed Central

    Guo, Ying; Palmer, J. Lynn; Brown, Xun S.; Fu, Jack B.

    2016-01-01

    Introduction The sural/radial nerve amplitude ratio (SRAR) is the quotient of the sensory nerve action potential (SNAP) amplitudes (Amp) of the sural and the superficial radial nerve. It has been hypothesized that this ratio can be used for the detection of early axonal loss, because the sural SNAP amplitude will decrease first, thereby also decreasing the SRAR value. Objectives To determine the sensitivity and specificity of SRAR, age-adjusted sural and radial SNAP Amp in the diagnosis of axonal sensory polyneuropathy in cancer patients. Design Retrospective review. Setting Comprehensive cancer center. Patients One hundred and ninety one EMG reports from January 2001 to December 2005. Methods The independent variable is the diagnosis of axonal sensory polyneuropathy in the EMG reports that is based on multiple tests. Main Outcome Measurements We assessed the agreement between classifications of axonal sensory polyneuropathy made using the current ‘gold standard’ and the proposed method that is based on patients’ age-adjusted radial and sural SNAP amplitude; an SRAR being above or below the normal value (0.21). Results We found that the sensitivities for age-adjusted radial SNAP Amp, age-adjusted sural SNAP Amp, and SRAR were 33%, 64%, 56% respectively; the specificities were 85%, 70%, 77% respectively. Conclusions SRAR is neither the most sensitive, nor the most specific in the diagnosis of axonal sensory polyneuropathy.

  20. [The characteristics of operator activity in a sensorially enriched environment].

    PubMed

    Pavlygina, R A; Frolov, M V; Davydov, V A; Milovanova, G B; Sulimov, A V

    1999-01-01

    The mechanism of Ukhtomski?'s dominant was used to improve operator's performance activity. Recognition of visual images--obscured Arabic numerals--in a sensorially rich environment (classic or rock music records) turned to be more successful: time of the task was reduced and the probability of correct identification increased. A reverse U-shaped dependence between the intensity of music and identification was stated. Repetition of music fragments at a constant value marred the positive effect. PMID:10656133

  1. Exploring the mammalian sensory space: co-operations and trade-offs among senses.

    PubMed

    Nummela, Sirpa; Pihlström, Henry; Puolamäki, Kai; Fortelius, Mikael; Hemilä, Simo; Reuter, Tom

    2013-12-01

    The evolution of a particular sensory organ is often discussed with no consideration of the roles played by other senses. Here, we treat mammalian vision, olfaction and hearing as an interconnected whole, a three-dimensional sensory space, evolving in response to ecological challenges. Until now, there has been no quantitative method for estimating how much a particular animal invests in its different senses. We propose an anatomical measure based on sensory organ sizes. Dimensions of functional importance are defined and measured, and normalized in relation to animal mass. For 119 taxonomically and ecologically diverse species, we can define the position of the species in a three-dimensional sensory space. Thus, we can ask questions related to possible trade-off vs. co-operation among senses. More generally, our method allows morphologists to identify sensory organ combinations that are characteristic of particular ecological niches. After normalization for animal size, we note that arboreal mammals tend to have larger eyes and smaller noses than terrestrial mammals. On the other hand, we observe a strong correlation between eyes and ears, indicating that co-operation between vision and hearing is a general mammalian feature. For some groups of mammals we note a correlation, and possible co-operation between olfaction and whiskers. PMID:24043357

  2. Judgments of dominance from the face track physical strength.

    PubMed

    Toscano, Hugo; Schubert, Thomas W; Sell, Aaron N

    2014-01-01

    It is commonly assumed that judgments of dominance from faces partly rely on implicit judgments of bodily strength. In two studies, we demonstrate such a relation for both computer-generated and natural photos of male faces. We find support when aggregating data across participants, when analyzing with hierarchical models, and also when strength and dominance are judged by different raters. Moreover, we identify common predictors that underlie perceptions of both strength and dominance: brow height, eye length, chin length, and the widths of the nose and mouth. PMID:24558653

  3. Sensory Transduction in Caenorhabditis elegans

    NASA Astrophysics Data System (ADS)

    Brown, Austin L.; Ramot, Daniel; Goodman, Miriam B.

    The roundworm Caenorhabditis elegans has a well-defined and comparatively simple repertoire of sensory-guided behaviors, all of which rely on its ability to detect chemical, mechanical or thermal stimuli. In this chapter, we review what is known about the ion channels that mediate sensation in this remarkable model organism. Genetic screens for mutants defective in sensory-guided behaviors have identified genes encoding channel proteins, which are likely transducers of chemical, thermal, and mechanical stimuli. Such classical genetic approaches are now being coupled with molecular genetics and in vivo cellular physiology to elucidate how these channels are activated in specific sensory neurons. The ion channel superfamilies implicated in sensory transduction in C. elegans - CNG, TRP, and DEG/ENaC - are conserved across phyla and also appear to contribute to sensory transduction in other organisms, including vertebrates. What we learn about the role of these ion channels in C. elegans sensation is likely to illuminate analogous processes in other animals, including humans.

  4. Crossmodal plasticity in sensory loss.

    PubMed

    Frasnelli, Johannes; Collignon, Olivier; Voss, Patrice; Lepore, Franco

    2011-01-01

    In this review, we describe crossmodal plasticity following sensory loss in three parts, with each section focusing on one sensory system. We summarize a wide range of studies showing that sensory loss may lead, depending of the affected sensory system, to functional changes in other, primarily not affected senses, which range from heightened to lowered abilities. In the first part, the effects of blindness on mainly audition and touch are described. The latest findings on brain reorganization in blindness are reported, with a particular emphasis on imaging studies illustrating how nonvisual inputs recruit the visually deafferented occipital cortex. The second part covers crossmodal processing in deafness, with a special focus on the effects of deafness on visual processing. In the last portion of this review, we present the effects that the loss of a chemical sense have on the sensitivity of the other chemical senses, that is, smell, taste, and trigeminal chemosensation. We outline how the convergence of the chemical senses to the same central processing areas may lead to the observed reduction in sensitivity of the primarily not affected senses. Altogether, the studies reviewed herein illustrate the fascinating plasticity of the brain when coping with sensory deprivation. PMID:21741555

  5. COMPU-EYE: a high resolution computational compound eye.

    PubMed

    Lee, Woong-Bi; Jang, Hwanchol; Park, Sangjun; Song, Young Min; Lee, Heung-No

    2016-02-01

    In nature, the compound eyes of arthropods have evolved towards a wide field of view (FOV), infinite depth of field and fast motion detection. However, compound eyes have inferior resolution when compared with the camera-type eyes of vertebrates, owing to inherent structural constraints such as the optical performance and the number of ommatidia. For resolution improvements, in this paper, we propose COMPUtational compound EYE (COMPU-EYE), a new design that increases acceptance angles and uses a modern digital signal processing (DSP) technique. We demonstrate that the proposed COMPU-EYE provides at least a four-fold improvement in resolution. PMID:26906778

  6. Single Ca2+ channels and exocytosis at sensory synapses

    PubMed Central

    Kim, Mean-Hwan; Li, Geng-Lin; von Gersdorff, Henrique

    2013-01-01

    Hair cell synapses in the ear and photoreceptor synapses in the eye are the first synapses in the auditory and visual system. These specialized synapses transmit a large amount of sensory information in a fast and efficient manner. Moreover, both small and large signals with widely variable kinetics must be quickly encoded and reliably transmitted to allow an animal to rapidly monitor and react to its environment. Here we briefly review some aspects of these primary synapses, which are characterized by a synaptic ribbon in their active zones of transmitter release. We propose that these synapses are themselves highly specialized for the task at hand. Photoreceptor and bipolar cell ribbon synapses in the retina appear to have versatile properties that permit both tonic and phasic transmitter release. This allows them to transmit changes of both luminance and contrast within a visual field at different ambient light levels. By contrast, hair cell ribbon synapses are specialized for a highly synchronous form of multivesicular release that may be critical for phase locking to low-frequency sound-evoked signals at both low and high sound intensities. The microarchitecture of a hair cell synapse may be such that the opening of a single Ca2+ channel evokes the simultaneous exocytosis of multiple synaptic vesicles. Thus, the differing demands of sensory encoding in the eye and ear generate diverse designs and capabilities for their ribbon synapses. PMID:23459757

  7. Eye and pit size are inversely correlated in crotalinae: Implications for selection pressure relaxation.

    PubMed

    Liu, Yang; Chen, Qin; Papenfuss, Theodore J; Lu, Fang; Tang, Yezhong

    2016-01-01

    Mate, prey, and predator recognition often depend on the integration of information from multiple sensory modalities including visual, auditory, and/or olfactory inputs. In Crotalinae, the eyes sense visible light while the pit organs detect infrared (IR) radiation. Previous studies indicate that there is significant overlap between the eye and pit sensory fields and that both senses are involved in recognition processes. This study investigated the relationships between eye and pit sizes in this taxonomic group as a function of phylogeny and habitat. In view of the fact that pit orientation depends largely on snout shape, pit vipers were grouped as follows: 1) arboreal, 2) terrestrial with rounded snout, and 3) terrestrial with pointed snout. The pit orientations and habitant patterns were fully independent of the Crotalinae phylogenetic tree. The phylogenetic generalized least squares model showed that both eye and pit areas were not of significantly phylogenetic relatedness, implying alternatively a strong effect of adaptation on eye and pit sizes. Negative correlations between relative eye and pit areas in terrestrial (both pointed and rounded snouts) and arboreal species were statistically significant. Our results suggest that the eyes and pits function in a complementary fashion such that selection for IR-perception relaxes selection pressures on the visual system and selection for visual discrimination relaxes selection pressures acting on the IR-system. J. Morphol. 277:107-117, 2016. © 2015 Wiley Periodicals, Inc. PMID:26442780

  8. Isoniazid induced motor-dominant neuropathy.

    PubMed

    Arsalan, Rabeeya; Sabzwari, Saniya

    2015-10-01

    Isoniazid though a very effective treatment for tuberculosis can cause severe motor-dominant neuropathy which can be reversible with pyridoxine supplementation. A 45-year-old female diagnosed with psoas abscess, culture positive for mycobacterium tuberculosis, was started on anti- tuberculous treatment with four drugs, including isoniazid at a dose of 5 mg/kg/day. Three months later she developed severe motor weakness of lower limbs with loss of ankle and knee reflexes. She was treated with vitamin B6 injections and isoniazid treatment was continued. Her motor weakness gradually improved in a few months, but mild sensory impairment persisted even after two years. There is need for vigilance regarding neurological effects of isoniazid in seemingly low-risk individuals in whom development of symptoms should raise the suspicion about slow acetylator status. Timely therapeutic intervention with high-dose vitamin B6 can reduce the long-term morbidity associated with this easily reversible condition. PMID:26440850

  9. Perceptual learning modifies untrained pursuit eye movements

    PubMed Central

    Szpiro, Sarit F. A.; Spering, Miriam; Carrasco, Marisa

    2014-01-01

    Perceptual learning improves detection and discrimination of relevant visual information in mature humans, revealing sensory plasticity. Whether visual perceptual learning affects motor responses is unknown. Here we implemented a protocol that enabled us to address this question. We tested a perceptual response (motion direction estimation, in which observers overestimate motion direction away from a reference) and a motor response (voluntary smooth pursuit eye movements). Perceptual training led to greater overestimation and, remarkably, it modified untrained smooth pursuit. In contrast, pursuit training did not affect overestimation in either pursuit or perception, even though observers in both training groups were exposed to the same stimuli for the same time period. A second experiment revealed that estimation training also improved discrimination, indicating that overestimation may optimize perceptual sensitivity. Hence, active perceptual training is necessary to alter perceptual responses, and an acquired change in perception suffices to modify pursuit, a motor response. PMID:25002412

  10. The neuroecology of cartilaginous fishes: sensory strategies for survival.

    PubMed

    Collin, Shaun P

    2012-01-01

    As apex predators, chondrichthyans, or cartilaginous fishes, hold an important position within a range of aquatic ecosystems and influence the balance between species' abundance and biodiversity. Having been in existence for over 400 million years and representing the earliest stages of the evolution of jawed vertebrates, this group also covers a diverse range of eco-morphotypes, occupying both marine and freshwater habitats. The class Chondrichthyes is divided into two subclasses: the Elasmobranchii (sharks, skates, and rays) and the Holocephali (elephant sharks and chimaeras). However, many of their life history traits, such as low fecundity, the production of small numbers of highly precocious young, slow growth rates, and late maturity, make them highly susceptible to human exploitation. To mitigate the negative effects of human impacts, it is important that we understand the sensory strategies that elasmobranchs use for navigating within their environment, forming reproductive aggregations, feeding, and even communicating. One approach to investigate the sensory bases of their behavior is to examine the peripheral sense organs mediating vision, olfaction, gustation, lateral line, electroreception, and audition in a large range of species in order to identify specific adaptations, the range of sensitivity thresholds, and the compromise between sensory spatial resolution and sensitivity. In addition, we can quantitatively assess the convergence of sensory input to the central nervous system and the relative importance of different sensory modalities. Using a comparative approach and often a combination of anatomical, electrophysiological, and molecular techniques, significant variation has been identified in the spatial and chromatic sampling of the photoreceptors in the eye, the surface area and the number of olfactory lamellae within the nasal cavity, the level of gustatory sampling within the oral cavity, the type and innervation of neuromasts of the lateral line system, the distribution of electroreceptive pores over the head, and the morphology of the inner ear. These results are presented in the context of predictions of sensory capabilities for species living in a range of ecological niches, what further research is needed, and how this sensory input may be a predictor of behavior. PMID:22986825

  11. Lymphocyte infiltration in CAPN5 autosomal dominant neovascular inflammatory vitreoretinopathy

    PubMed Central

    Mahajan, Vinit B; Lin, Jonathan H

    2013-01-01

    Purpose To describe immunohistopathological findings in autosomal dominant neovascular inflammatory vitreoretinopathy (ADNIV). Methods An enucleated eye specimen from a patient with Stage V ADNIV was examined using standard histopathological methods and lymphocyte markers. Results A c.731T>C CAPN5 mutation resulted in a p.Leu244Pro substitution in calpain-5. The eye showed exudative retinal detachment and neovascularization, intraocular fibrosis, and features of phthisis bulbi. Chronic inflammatory CD3-positive cell infiltrates were identified throughout the uvea, vitreous and retina, consistent with chronic uveitis. Conclusion Mutations in CAPN5 trigger autoimmune uveitis characterized by inflammatory T-cells and severe neovascularization. PMID:23861576

  12. Penetrating eye injuries.

    PubMed

    Patel, B C

    1989-03-01

    A review of all penetrating eye injuries treated at the Manchester Royal Eye Hospital over four years (1 January 1982-31 December 1985) was undertaken. A total of 202 penetrating eye injuries were seen of which 68 (34%) were in children under the age of 15 years. Airgun, dart, and knife injuries accounted for 28 (41%) of the injuries. Thirty seven patients (54%) achieved a good visual result (6/12 or better) and eight (12%) had enucleations. The period of inpatient treatment ranged from two to 18 days. From the analysis of the activities at the time of the injury, many of the injuries can be considered to be preventable. PMID:2705791

  13. Epac activation sensitizes rat sensory neurons through activation of Ras.

    PubMed

    Shariati, Behzad; Thompson, Eric L; Nicol, Grant D; Vasko, Michael R

    2016-01-01

    Guanine nucleotide exchange factors directly activated by cAMP (Epacs) have emerged as important signaling molecules mediating persistent hypersensitivity in animal models of inflammation, by augmenting the excitability of sensory neurons. Although Epacs activate numerous downstream signaling cascades, the intracellular signaling which mediates Epac-induced sensitization of capsaicin-sensitive sensory neurons remains unknown. Here, we demonstrate that selective activation of Epacs with 8-CPT-2'-O-Me-cAMP-AM (8CPT-AM) increases the number of action potentials (APs) generated by a ramp of depolarizing current and augments the evoked release of calcitonin gene-related peptide (CGRP) from isolated rat sensory neurons. Internal perfusion of capsaicin-sensitive sensory neurons with GDP-βS, substituted for GTP, blocks the ability of 8CPT-AM to increase AP firing, demonstrating that Epac-induced sensitization is G-protein dependent. Treatment with 8CPT-AM activates the small G-proteins Rap1 and Ras in cultures of sensory neurons. Inhibition of Rap1, by internal perfusion of a Rap1-neutralizing antibody or through a reduction in the expression of the protein using shRNA does not alter the Epac-induced enhancement of AP generation or CGRP release, despite the fact that in most other cell types, Epacs act as Rap-GEFs. In contrast, inhibition of Ras through expression of a dominant negative Ras (DN-Ras) or through internal perfusion of a Ras-neutralizing antibody blocks the increase in AP firing and attenuates the increase in the evoked release of CGRP induced by Epac activation. Thus, in this subpopulation of nociceptive sensory neurons, it is the novel interplay between Epacs and Ras, rather than the canonical Epacs and Rap1 pathway, that is critical for mediating Epac-induced sensitization. PMID:26596174

  14. Autosomal dominant cerebellar ataxias.

    PubMed

    Marelli, C; Cazeneuve, C; Brice, A; Stevanin, G; Dürr, A

    2011-05-01

    Cerebellar ataxias with autosomal dominant transmission (ADCA) are far rarer than sporadic cases of cerebellar ataxia. The identification of genes involved in dominant forms has confirmed the genetic heterogeneity of these conditions and of the underlying mechanisms and pathways. To date, at least 28 genetic loci and, among them, 20 genes have been identified. In many instances, the phenotype is not restricted to cerebellar dysfunction but includes more complex multisystemic neurological deficits. Seven ADCA (SCA1, 2, 3, 6, 7, 17, and dentatorubro-pallido-luysian atrophy) are caused by repeat expansions in the corresponding proteins; phenotype-genotype correlations have shown that repeat size influences the progression of the disease, its severity and clinical differences among patients, including the phenomenon of anticipation between generations. All other ADCA are caused either by non-coding repeat expansions, conventional mutations or large rearrangements in genes with different functions. This review will focus on the genetic features of ADCA and on the clinical differences among the different forms. PMID:21546047

  15. Photorefraction of the Eye

    NASA Astrophysics Data System (ADS)

    Colicchia, Giuseppe; Wiesner, Hartmut; Zollman, Dean

    2015-02-01

    Photorefraction is a method to easily estimate the refractive state of the eye. The principle of photorefraction involves projecting light into the eye during flash photography and then examining the paths of light that emerge from the pupil after scattering on the back portion of the interior of the eyeball (fundus). We will explain the optical principles underlying the method for eccentric photorefraction and describe how students can perform it using current digital cameras. Our purpose is not to diagnose refractive errors reliably, but to use devices popular among young people that, in combination with an important ophthalmic context, may be successful in improving students' interest for learning optical concepts.

  16. Wayfinding and eye movements

    NASA Astrophysics Data System (ADS)

    Kim, Nam-Gyoon

    1997-06-01

    During rectilinear locomotion, the focus of expansion identifies the observer's heading. Eye rotation or curvilinear locomotion annihilates this singularity. Computer simulations of eye rotation during circular translation present possible solutions to heading judgement. Specifically, when gaze direction coincides with circular heading, every velocity vector in the image plane becomes linearized. These velocity vectors are tangent vectors of the corresponding flow lines of optical flow. Moreover, the vectors corresponding to the observer's path are all aligned perpendicularly in the image plane, which in turn can be used to determine the observer's path of locomotion.

  17. Sensory Neuronopathy and Autoimmune Diseases

    PubMed Central

    Martinez, Alberto R. M.; Nunes, Marcelo B.; Nucci, Anamarli; França, Marcondes C.

    2012-01-01

    Sensory neuronopathies (SNs) are a specific subgroup of peripheral nervous system diseases characterized by primary degeneration of dorsal root ganglia and their projections. Multifocal sensory symptoms often associated to ataxia are the classical features of SN. Several different etiologies have been described for SNs, but immune-mediated damage plays a key role in most cases. SN may herald the onset of some systemic autoimmune diseases, which further emphasizes how important the recognition of SN is in clinical practice. We have thus reviewed available clinical, neurophysiological, and therapeutic data on autoimmune disease-related SN, namely, in patients with Sjögren's syndrome, autoimmune hepatitis, and celiac disease. PMID:22312482

  18. Vision impairment and dual sensory problems in middle age

    PubMed Central

    Dawes, Piers; Dickinson, Christine; Emsley, Richard; Bishop, Paul; Cruickshanks, Karen; Edmondson-Jones, Mark; McCormack, Abby; Fortnum, Heather; Moore, David R.; Norman, Paul; Munro, Kevin

    2014-01-01

    Purpose Vision and hearing impairments are known to increase in middle age. In this study we describe the prevalence of vision impairment and dual sensory impairment in UK adults aged 40 to 69 years in a very large and recently ascertained data set. The associations between vision impairment, age, sex, socioeconomic status, and ethnicity are reported. Methods This research was conducted using the UK Biobank Resource, with subsets of UK Biobank data analysed with respect to self-report of eye problems and glasses use. Better-eye visual acuity with habitually worn refractive correction was assessed with a logMAR chart (n = 116,682). Better-ear speech reception threshold was measured with an adaptive speech in noise test, the Digit Triplet Test (n = 164,770). Prevalence estimates were weighted with respect to UK 2001 Census data. Results Prevalence of mild visual impairment and low vision was estimated at 15.2% (95% CI 14.9–15.5%) and 0.9% (95% CI 0.8–1.0%), respectively. Use of glasses was 88.0% (95% CI 87.9–88.1%). The prevalence of dual sensory impairment was 3.1% (95% CI 3.0–3.2%) and there was a nine-fold increase in the prevalence of dual sensory problems between the youngest and oldest age groups. Older adults, those from low socioeconomic and ethnic minority backgrounds were most at risk for vision problems. Conclusions Mild vision impairment is common in middle aged UK adults, despite widespread use of spectacles. Possible barriers to optometric care for those from low socioeconomic and ethnic minority backgrounds may require attention. A higher than expected prevalence of dual impairment suggests that hearing and vision problems share common causes. Optometrists should consider screening for hearing problems, particularly among older adults. PMID:24888710

  19. Relative eye size in elasmobranchs.

    PubMed

    Lisney, Thomas J; Collin, Shaun P

    2007-01-01

    Variation in relative eye size was investigated in a sample of 46 species of elasmobranch, 32 species of sharks and 14 species of batoids (skates and rays). To get a measure of eye size relative to body size, eye axial diameter was scaled with body mass using least-squares linear regression, using both raw species data, where species are treated as independent data points, and phylogenetically independent contrasts. Residual values calculated for each species, using the regression equations describing these scaling relationships, were then used as a measure of relative eye size. Relative and absolute eye size varies considerably in elasmobranchs, although sharks have significantly relatively larger eyes than batoids. The sharks with the relatively largest eyes are oceanic species; either pelagic sharks that move between the epipelagic (0-200 m) and 'upper' mesopelagic (200-600 m) zones, or benthic and benthopelagic species that live in the mesopelagic (200-1,000 m) and, to a lesser extent, bathypelagic (1,000-4,000 m) zones. The elasmobranchs with the relatively smallest eyes tend to be coastal, often benthic, batoids and sharks. Active benthopelagic and pelagic species, which prey on active, mobile prey also have relatively larger eyes than more sluggish, benthic elasmobranchs that feed on more sedentary prey such as benthic invertebrates. A significant positive correlation was found between absolute eye size and relative eye size, but some very large sharks, such as Carcharodon carcharias have absolutely large eyes, but have relatively small eyes in relation to body mass. PMID:17314474

  20. Rings dominate western Gulf

    NASA Astrophysics Data System (ADS)

    Vidal L., Francisco V.; Vidal L., Victor M. V.; Molero, José María Pérez

    Surface and deep circulation of the central and western Gulf of Mexico is controlled by interactions of rings of water pinched from the gulf's Loop Current. The discovery was made by Mexican oceanographers who are preparing a full-color, 8-volume oceanographic atlas of the gulf.Anticyclonic warm-core rings pinch off the Loop Current at a rate of about one to two per year, the scientists of the Grupo de Estudios Oceanográficos of the Instituto de Investigaciones Eléctricas (GEO-IIE) found. The rings migrate west until they collide with the continental shelf break of the western gulf, almost always between 22° and 23°N latitude. On their westward travel they transfer angular momentum and vorticity to the surrounding water, generating cyclonic circulations and vortex pairs that completely dominate the entire surface and deep circulation of the central and western gulf.

  1. Molecular restrictions for human eye irritation by chemical vapors

    SciTech Connect

    Cometto-Muniz, J. Enrique . E-mail: ecometto@ucsd.edu; Cain, William S.; Abraham, Michael H.

    2005-09-15

    Previous research showed a cut-off along homologous volatile organic compounds (VOCs) in their ability to produce acute human mucosal irritation. The present study sought to specify the particular cut-off homolog for sensory eye irritation in an acetate and n-alcohol series. A 1900-ml glass vessel system and a three-alternative forced-choice procedure served to test nonyl, decyl, and dodecyl acetate, and 1-nonanol, 1-decanol, and 1-undecanol. Flowrate to the eye ranged from 2 to 8 L/min and time of exposure from 3 to 24 s. Decyl acetate and 1-undecanol were the shortest homologs that failed to produce eye irritation under all conditions, producing a cut-off effect. Increasing the vapor concentration of decyl acetate and 1-undecanol by 3 and 8 times, respectively, via heating them to 37 deg C made either or both VOCs detectable to only half of the 12 subjects tested, even though the higher vapor concentration was well above a predicted eye irritation threshold. When eye irritation thresholds for homologous acetates and n-alcohols were plotted as a function of the longest unfolded length of the molecule, the values for decyl acetate and 1-undecanol fell within a restricted range of 18 to 19 A. The outcome suggests that the basis for the cut-off is biological, that is, the molecule lacks a key size or structure to trigger transduction, rather than physical, that is, the vapor concentration is too low to precipitate detection.

  2. Pursuit Eye Movements

    NASA Technical Reports Server (NTRS)

    Krauzlis, Rich; Stone, Leland; Null, Cynthia H. (Technical Monitor)

    1998-01-01

    When viewing objects, primates use a combination of saccadic and pursuit eye movements to stabilize the retinal image of the object of regard within the high-acuity region near the fovea. Although these movements involve widespread regions of the nervous system, they mix seamlessly in normal behavior. Saccades are discrete movements that quickly direct the eyes toward a visual target, thereby translating the image of the target from an eccentric retinal location to the fovea. In contrast, pursuit is a continuous movement that slowly rotates the eyes to compensate for the motion of the visual target, minimizing the blur that can compromise visual acuity. While other mammalian species can generate smooth optokinetic eye movements - which track the motion of the entire visual surround - only primates can smoothly pursue a single small element within a complex visual scene, regardless of the motion elsewhere on the retina. This ability likely reflects the greater ability of primates to segment the visual scene, to identify individual visual objects, and to select a target of interest.

  3. Eye of the Beholder

    ERIC Educational Resources Information Center

    Rogers, Michael

    2010-01-01

    Art, like beauty, as the adage goes, is in the eye of the beholder. Art also is a living, breathing thing that evolves over time, so what is considered "art" is ever changing--how many of the great artists whose works today sell for fortunes were failures during their lifetime? The 20th century unknowingly gave birth to new variations of art that…

  4. The Eyes Have It

    NASA Technical Reports Server (NTRS)

    1999-01-01

    NASA'S Ames Research Center contracted with SRI international to contract a device that would be able to anticipate, track, and monitor involuntary ocular movement horizontally, vertically, and with respect to depth-of-field. This development helped research institutions to understand the eye. The Eyetracker, manufactured and distributed by Forward Optical Technologies, Inc. is now used in the clinical/medical field.

  5. Diabetic Eye Disease

    MedlinePLUS

    ... Your Doctor Financial Aid for Eye Care En español La enfermedad diabética del ojo La enfermedad diabética ... Z Site Map Information in Spanish (Información en español) Website, Social Media Policies and Other Important Links ...

  6. Eye of the Beholder

    ERIC Educational Resources Information Center

    Rogers, Michael

    2010-01-01

    Art, like beauty, as the adage goes, is in the eye of the beholder. Art also is a living, breathing thing that evolves over time, so what is considered "art" is ever changing--how many of the great artists whose works today sell for fortunes were failures during their lifetime? The 20th century unknowingly gave birth to new variations of art that…

  7. Administering Eye Medications.

    ERIC Educational Resources Information Center

    Morris, Sara; Michael, Nancy, Ed.

    This module on administering eye medications is intended for use in inservice or continuing education programs for persons who administer medications in long-term care facilities. Instructor information, including teaching suggestions, and a listing of recommended audiovisual materials and their sources appear first. A brief discussion follows of…

  8. Through Our Eyes

    ERIC Educational Resources Information Center

    Narva, Sara

    2009-01-01

    Through Our Eyes was a multimedia performance created in collaboration with the author's five modern dance students. Through video, sound, and dance, the piece shows some ways race has affected their lives. The author did not set out at the beginning of the semester to make this project in her dance class. It was born out of a hard conversation,…

  9. Preventing Eye Injuries

    MedlinePLUS

    ... yard work, cleaning and cooking. More than a third (34.2 percent) of injuries in the home occurred in living areas such as the kitchen, bedroom, bathroom, living or family room. More than 40 percent of eye injuries every year are related to sports or ...

  10. Through Students' Eyes.

    ERIC Educational Resources Information Center

    McLean-Donaldson, Karen B.

    1994-01-01

    Identifies how students perceive racism and its effects on student learning and whether antiracist/multicultural arts (ARMA) curricula can empower students to address racism in schools. Results show racism, through students' eyes, damages learning, attitudes, and behavior. ARMA positively effected students' ability to confront racism within their…

  11. Galileo's eye: a new vision of the senses in the work of Galileo Galilei.

    PubMed

    Piccolino, Marco; Wade, Nicholas J

    2008-01-01

    Reflections on the senses, and particularly on vision, permeate the writings of Galileo Galilei, one of the main protagonists of the scientific revolution. This aspect of his work has received scant attention by historians, in spite of its importance for his achievements in astronomy, and also for the significance in the innovative scientific methodology he fostered. Galileo's vision pursued a different path from the main stream of the then contemporary studies in the field; these were concerned with the dioptrics and anatomy of the eye, as elaborated mainly by Johannes Kepler and Christoph Scheiner. Galileo was more concerned with the phenomenology rather than with the mechanisms of the visual process. His general interest in the senses was psychological and philosophical; it reflected the fallacies and limits of the senses and the ways in which scientific knowledge of the world could be gathered from potentially deceptive appearances. Galileo's innovative conception of the relation between the senses and external reality contrasted with the classical tradition dominated by Aristotle; it paved the way for the modern understanding of sensory processing, culminating two centuries later in Johannes Müller's elaboration of the doctrine of specific nerve energies and in Helmholtz's general theory of perception. PMID:18986060

  12. Sensory functions of motile cilia and implication for bronchiectasis

    PubMed Central

    Jain, Raksha; Javidan-Nejad, Cylen; Alexander-Brett, Jennifer; Horani, Amjad; Cabellon, Michelle C.; Walter, Michael J.; Brody, Steven L.

    2013-01-01

    Cilia are specialized organelles that extend from the surface of cells into the local environment. Airway epithelial cell cilia are motile to provide mucociliary clearance for host defense. On other cells, solitary cilia are specialized to detect chemical or mechanosensory signals. Sensory proteins in motile cilia have recently been identified that detect shear stress, osmotic force, fluid flow, bitter taste and sex hormones. The relationship of sensory function in human motile cilia to disease is now being revealed. One example is polycystin-1 and polycystin-2. As a complex, these proteins function as a flow sensor in cilia and are mutated in autosomal dominant polycystic kidney disease (ADPKD). The polycystins are also expressed in motile cilia of the airways, potentially operating as sensors in the lung. Computed tomography studies from patients with ADPKD revealed radiographic evidence for bronchiectasis, suggesting that polycystin-1 and -2 are important in lung function. The expression of this complex and sensory channel TRPV4, and bitter taste and sex hormones receptors in motile cilia indicate that the cell is wired to interpret environmental cues to regulate cilia beat frequency and other functions. Defective signaling of sensory proteins may result in a ciliopathy that includes lung disease. PMID:22202111

  13. Multimodal Sensory Distortions in Post-partum Exacerbation of Schizophrenia.

    PubMed

    Mehta, Urvakhsh Meherwan; Naveen Kumar, C; Venkatasubramanian, Ganesan; Thirthalli, Jagadisha

    2013-11-25

    Background: Sensory distortions of body image commonly occur during migraine, seizures, non-dominant cortical infarcts and hallucinogen abuse.Methods: We report the case of a 30-year-old woman with paranoid schizophrenia, presenting with post-partum onset multimodal sensory distortions in the absence of any neurological disorders or substance use.Results: Her symptoms involved persistent facial/body metamorphopsia (distorted images) and vocal paracousis (distorted voices), in the absence of visual hallucinations, illusions or agnosia. Neuropsychological assessments revealed deficits on visual processing tasks. Neuroimaging, electroencephalography and ophthalmological evaluation revealed no abnormalities. The multimodal sensory distortions responded to anti-psychotic treatment, paralleling improvement in other schizophrenia psychopathology, over a period of one month.Conclusion: Prominent and persistent multimodal sensory distortions like metamorphopsia and paracousis in the presence of psychotic symptoms warrant a detailed neurological and general medical work-up. These symptoms presenting in the absence of neurological or substance use disorders may be a component of schizophrenia. PMID:24275634

  14. Enhanced visual dominance in far space.

    PubMed

    Yue, Zhenzhu; Jiang, Yizhou; Li, You; Wang, Pengfei; Chen, Qi

    2015-10-01

    The Colavita effect refers to the phenomenon that people do not respond to an auditory stimulus in most cases when a visual stimulus is simultaneously presented. Although the Colavita effect remains robust irrespective of many factors, little is known concerning how the visual dominance varies as a function of the depth of sensory inputs. In the present study, visual and auditory stimuli were presented either in the same (in Experiment 1) or in the different spatial distances (in Experiment 2). Participants were asked to make speeded responses to unimodal auditory, unimodal visual, or bimodal audiovisual stimuli. In the incorrectly responded bimodal trials, the error trials in which responses were made only to the visual component were compared with the trials in which responses were made only to the auditory component. In the correctly responded bimodal trials, the trials in which participants responded first to the visual component were compared with the trials in which participants responded first to the auditory component. Analysis on the incorrect and correct bimodal trials both indicated significant visual dominance effects. More importantly, the size of the visual dominance effect was significantly enhanced as long as the visual stimuli were presented in far space irrespective of whether the auditory stimuli were presented in near or far space. Our results thus, for the first time, revealed that the visual dominance effect changed along the depth dimension of space. Taken together, the present results shed lights on how the allocation of attentional resources along the depth dimension of space biases the process of multisensory competition. PMID:26080757

  15. Infographic on the Aging Eye

    MedlinePLUS

    ... retina. Dry eye Low vision Damage to the optic nerve. Eyes do not make enough tears. Difficulty ... retina that can be seen through undilated pupil. OPTIC NERVE RAY OF LIGHT PUPIL RETINA Portion of ...

  16. Conjunctivitis: What Is Pink Eye?

    MedlinePLUS

    ... Health News Consumer Alerts Conjunctivitis: What Is Pink Eye? Tweet Conjunctivitis is the term used to describe ... that Led to a Diabetes Diagnosis Find An Eye M.D. Enter zip code here Search by ...

  17. Eye Bank Association of America

    MedlinePLUS

    ... We Are What We Do Cornea Donation Volunteer Leadership Board of Directors Committees Staff Find an Eye ... We Are What We Do Cornea Donation Volunteer Leadership Board of Directors Committees Staff Find an Eye ...

  18. Simple Solutions for Dry Eye

    MedlinePLUS

    ... and can irritate the eye. • Use non-preserved artificial tears frequently and regularly, even when your eyes ... are uncomfortable. • When starting a new, preservative-free artificial tear, use the drops every 1-2 hours ...

  19. Medicare Benefits and Your Eyes

    MedlinePLUS

    ... cover eyeglasses or contact lenses, except immediately following cataract surgery. Medicare does cover an eye exam for ... at risk for developing diabetic retinopathy, glaucoma, and cataracts. Diabetic Eye Disease can affect anyone with diabetes. ...

  20. Age-related changes in human posture control: Sensory organization tests

    NASA Technical Reports Server (NTRS)

    Peterka, R. J.; Black, F. O.

    1989-01-01

    Postural control was measured in 214 human subjects ranging in age from 7 to 81 years. Sensory organization tests measured the magnitude of anterior-posterior body sway during six 21 s trials in which visual and somatosensory orientation cues were altered (by rotating the visual surround and support surface in proportion to the subject's sway) or vision eliminated (eyes closed) in various combinations. No age-related increase in postural sway was found for subjects standing on a fixed support surface with eyes open or closed. However, age-related increases in sway were found for conditions involving altered visual or somatosensory cues. Subjects older than about 55 years showed the largest sway increases. Subjects younger than about 15 years were also sensitive to alteration of sensory cues. On average, the older subjects were more affected by altered visual cues whereas younger subjects had more difficulty with altered somatosensory cues.

  1. [Sensory Awareness through Outdoor Education].

    ERIC Educational Resources Information Center

    Farquhar, Carin; And Others

    Designed for instruction of emotionally handicapped children and youth, these seven articles present concepts and activities relative to sensory awareness and outdoor education. The first article presents definitions, concepts, detailed methodology, and over 50 activities designed to create awareness of man's five senses. Utilizing the art of…

  2. The epidermis: a sensory tissue.

    PubMed

    Boulais, Nicholas; Misery, Laurent

    2008-01-01

    The skin is an efficient barrier which protects our bodies from the external environment but it is also an important site for the perception of various stimuli. Sensory neurones of the peripheral nervous system send many primary afferent fibres to the skin. They pass through the dermis and penetrate the basement membrane to innervate epidermal cells or remain as free endings. Nerve fibres are clearly involved in somatosensation. However, they are not always so numerous, for example in distal parts of the limbs, and some kinds of sensors can be at a distance of hundreds of micrometers from each other. The skin can detect patterns at a very fine and smaller scale, which suggests that nerve terminals are helped by epidermal sensors. All epidermal cells (keratinocytes, melanocytes, Langerhans cells and Merkel cells) express sensor proteins and neuropeptides regulating the neuro-immuno-cutaneous system. Hence, they must play a part in the epidermal sensory system. This review will consider the epidermal components of this forefront sensory system and the stimulations they perceive. The epidermis can be considered a true sensory tissue where sensor proteins and neurone-like properties enable epidermal cells to participate in the skin surface perception through interactions with nerve fibres. PMID:18424369

  3. Making Sense of Sensory Systems

    ERIC Educational Resources Information Center

    Hendrix, Marie

    2010-01-01

    The role of caregivers requires that they continuously assess the needs and performance of children and provide the support necessary for them to achieve their potential. A thorough understanding of child development, including the role and impact of sensory development, is critical for caregivers to properly evaluate and assist these children.…

  4. Making Sense of Sensory Systems

    ERIC Educational Resources Information Center

    Hendrix, Marie

    2010-01-01

    The role of caregivers requires that they continuously assess the needs and performance of children and provide the support necessary for them to achieve their potential. A thorough understanding of child development, including the role and impact of sensory development, is critical for caregivers to properly evaluate and assist these children.…

  5. Vasopressin and sensory circumventricular organs.

    PubMed

    Jurzak, M; Schmid, H A

    1998-01-01

    The subfornical organ, the area postrema and the organum vasculosum of the lamina terminalis are considered to be sensory circumventricular organs as they contain neuronal somata which are located outside the blood-brain barrier and are thus capable of serving as 'sensors' for blood-borne humoral messengers. The endocrine hormone, vasopressin (VP), not only causes strong antidiuresis by acting on the kidney, but also exerts centrally mediated effects as a neuromodulator. Several lines of evidence suggest that VP can influence regulatory functions mediated by the sensory circumventricular organs, since vasopressinergic somata and terminals as well as VP receptors have been reposted to be present in these structures. These biochemical prerequisites offer the possibility that blood-borne VP might on the one hand act as a feedback signal from the periphery and, on the other hand, synaptically released or locally produced VP could modulate the known functions of sensory circumventricular organs, such as thirst, fever or cardiovascular regulation. This review focuses on the possible physiological relevance of VP acting on sensory circumventricular organs in view of recent evidence obtained from biochemical and electrophysiological studies at the cellular level. PMID:10074791

  6. Sensory Aids for the Blind.

    ERIC Educational Resources Information Center

    National Academy of Sciences - National Research Council, Washington, DC. Committee on Prosthetics Research and Development.

    The problems of providing sensory aids for the blind are presented and a report on the present status of aids discusses direct translation and recognition reading machines as well as mobility aids. Aspects of required research considered are the following: assessment of needs; vision, audition, taction, and multimodal communication; reading aids,…

  7. Predictive eye movements in natural vision

    PubMed Central

    McKinney, Travis; Chajka, Kelly; Pelz, Jeff B.

    2012-01-01

    In the natural world, the brain must handle inherent delays in visual processing. This is a problem particularly during dynamic tasks. A possible solution to visuo-motor delays is prediction of a future state of the environment based on the current state and properties of the environment learned from experience. Prediction is well known to occur in both saccades and pursuit movements and is likely to depend on some kind of internal visual model as the basis for this prediction. However, most evidence comes from controlled laboratory studies using simple paradigms. In this study, we examine eye movements made in the context of demanding natural behavior, while playing squash. We show that prediction is a pervasive component of gaze behavior in this context. We show in addition that these predictive movements are extraordinarily precise and operate continuously in time across multiple trajectories and multiple movements. This suggests that prediction is based on complex dynamic visual models of the way that balls move, accumulated over extensive experience. Since eye, head, arm, and body movements all co-occur, it seems likely that a common internal model of predicted visual state is shared by different effectors to allow flexible coordination patterns. It is generally agreed that internal models are responsible for predicting future sensory state for control of body movements. The present work suggests that model-based prediction is likely to be a pervasive component in natural gaze control as well. PMID:22183755

  8. Eye color as an indicator of social rank in the fish Nile tilapia.

    PubMed

    Volpato, G L; Luchiari, A C; Duarte, C R A; Barreto, R E; Ramanzini, G C

    2003-12-01

    We investigated the association of eye color with the dominant-subordinate relationship in the fish Nile tilapia, Oreochromis niloticus. Eye color pattern was also examined in relation to the intensity of attacks. We paired 20 size-matched fish (intruder: 73.69 11.49 g; resident: 75.42 8.83 g) and evaluated eye color and fights. These fish were isolated in individual aquaria for 10 days and then their eye color was measured 5 min before pairing (basal values). Twenty minutes after pairing, eye color and fights were quantified for 10 min. Clear establishment of social hierarchy was observed in 7 of 10 pairs of fish. Number of attacks ranged from 1 to 168 among pairs. The quartile was calculated for these data and the pairs were then divided into two classes: low-attack (1 to 111 attacks - 2 lower quartiles) or high-attack (112 to 168 attacks - 2 higher quartiles). Dominance decreased the eye-darkening patterns of the fish after pairing, while subordinance increased darkening compared to dominance. Subordinate fish in low-attack confrontations presented a darker eye compared to dominant fish and to the basal condition. We also observed a paler eye pattern in dominants that shared low-attack interactions after pairing compared to the subordinates and within the group. However, we found no differences in the darkening pattern between dominants and subordinates from the high-attack groups. We conclude that eye color is associated with social rank in this species. Moreover, the association between eye color and social rank in the low-attack pairs may function to reduce aggression. PMID:14666250

  9. LIMNOLOGICAL OPTOMETRY: EXAMINING EARTH'S EYE

    EPA Science Inventory

    In Thoreau's Walden, a lake is described as the landscape's most expressive feature and the earth's eye. Collectively, scientists are charged by society to assess, monitor, and remedy maladies of earth's eye in the same way optometrists maintain the health of the human eye. This ...

  10. Experiments on a Model Eye

    ERIC Educational Resources Information Center

    Arell, Antti; Kolari, Samuli

    1978-01-01

    Explains a laboratory experiment dealing with the optical features of the human eye. Shows how to measure the magnification of the retina and the refractive anomaly of the eye could be used to measure the refractive power of the observer's eye. (GA)

  11. Can sensory attention focused exercise facilitate the utilization of proprioception for improved balance control in PD?

    PubMed

    Lefaivre, Shannon C; Almeida, Quincy J

    2015-02-01

    Impaired sensory processing in Parkinson's disease (PD) has been argued to contribute to balance deficits. Exercises aimed at improving sensory feedback and body awareness have the potential to ameliorate balance deficits in PD. Recently, PD SAFEx™, a sensory and attention focused rehabilitation program, has been shown to improve motor deficits in PD, although balance control has never been evaluated. The objective of this study was to measure the effects of PD SAFEx™ on balance control in PD. Twenty-one participants with mild to moderate idiopathic PD completed 12 weeks of PD SAFEx™ training (three times/week) in a group setting. Prior to training, participants completed a pre-assessment evaluating balance in accordance with an objective, computerized test of balance (modified clinical test of sensory integration and balance (m-CTSIB) and postural stability testing (PST)) protocols. The m-CTSIB was our primary outcome measure, which allowed assessment of balance in both eyes open and closed conditions, thus enabling evaluation of specific sensory contributions to balance improvement. At post-test, a significant interaction between time of assessment and vision condition (p=.014) demonstrated that all participants significantly improved balance control, specifically when eyes were closed. Balance control did not change from pre to post with eyes open. These results provide evidence that PD SAFEx™ is effective at improving the ability to utilize proprioceptive information, resulting in improved balance control in the absence of vision. Enhancing the ability to utilize proprioception for individuals with PD is an important intermediary to improving balance deficits. PMID:25655836

  12. A patient with loss of vision in the right eye and neurofibromatosis type 1

    PubMed Central

    Mumoli, Nicola; Cei, Marco; Bartolomei, Carlo; Pirillo, Vania

    2009-01-01

    Abstract: Neurofibromatosis type 1 is a common autosomal dominant condition that affects about 1 in 5000 people. We describe a 75-year-old man who, in addition to many classic developmental changes of the disease in his skin, eyes and nervous system, had blindness in his right eye as a complication. PMID:19153396

  13. A patient with loss of vision in the right eye and neurofibromatosis type 1.

    PubMed

    Mumoli, Nicola; Cei, Marco; Bartolomei, Carlo; Pirillo, Vania

    2009-01-20

    Neurofibromatosis type 1 is a common autosomal dominant condition that affects about 1 in 5000 people. We describe a 75-year-old man who, in addition to many classic developmental changes of the disease in his skin, eyes and nervous system, had blindness in his right eye as a complication. PMID:19153396

  14. Multi-Sensory Intervention Observational Research

    ERIC Educational Resources Information Center

    Thompson, Carla J.

    2011-01-01

    An observational research study based on sensory integration theory was conducted to examine the observed impact of student selected multi-sensory experiences within a multi-sensory intervention center relative to the sustained focus levels of students with special needs. A stratified random sample of 50 students with severe developmental…

  15. Response to Vestibular Sensory Events in Autism

    ERIC Educational Resources Information Center

    Kern, Janet K.; Garver, Carolyn R.; Grannemann, Bruce D.; Trivedi, Madhukar H.; Carmody, Thomas; Andrews, Alonzo A.; Mehta, Jyutika A.

    2007-01-01

    The purpose of this study was to examine the response to vestibular sensory events in persons with autism. The data for this study was collected as part of a cross-sectional study that examined sensory processing (using the Sensory Profile) in 103 persons with autism, 3-43 years of age, compared to age- and gender-matched community controls. The…

  16. USE OF SENSORY EVOKED POTENTIALS IN TOXICOLOGY

    EPA Science Inventory

    The rationale for studying sensory systems as an integral part of neurotoxicological examinations is presented. The role of evoked potentials in assessing brain dysfunction in general and sensory systems in particular is also presented. Four types of sensory evoked potentials (br...

  17. Contact Lens-Related Eye Infections

    MedlinePLUS

    ... Prevention News Ask an Eye M.D. Español Contact Lens-Related Eye Infections Contact Lens-Related Eye ... About Contact Lenses Proper Care of Contact Lenses Contact Lens-Related Eye Infections Written by: Kierstan Boyd ...

  18. Thyroid Eye Disease.

    PubMed

    Cornblath

    2000-09-01

    The treatment of thyroid eye disease is very complex, owing to the varied nature of the symptoms and the variable course of the disease. The first step in treatment should be achieving an euthyroid state or monitoring for the development of hyperthyroidism if the patient is euthyroid at presentation. The second step is local measures (artificial tears and ointment, cessation of smoking) along with careful visual follow-up (acuity, color vision, automated visual fields, fundus examination, ocular motility, and external examination) to assess for the development of optic neuropathy, proptosis, diplopia, and lid abnormalities. If external irritation or orbital discomfort cannot be managed with conservative local measures, then a trial of oral corticosteroids or orbital radiation can be considered. If optic neuropathy develops without proptosis, corticosteroids--starting with an intravenous course, then oral medication--should be used. If there is either an initial improvement in optic neuropathy with corticosteroids, but worsening with subsequent tapering of corticosteroids or no initial improvement, radiation treatment or orbital decompression can be done. If optic neuropathy develops with proptosis, corticosteroids--starting with an intravenous course, then oral medication--should be used for rapid visual improvement. Orbital decompression should then be done to resolve both the optic neuropathy and the proptosis. If for medical reasons the patient with optic neuropathy and proptosis is not a surgical candidate, then radiation treatment can be done, but there will be little change in the proptosis. Proptosis without optic neuropathy can be treated with orbital decompression both for cosmetic reasons and for comfort. Occasionally, this will also resolve lid retraction, and return the lids to an acceptable position in terms of cosmesis and corneal exposure. Diplopia is best treated initially with press-on prisms or patching. Once the disease is stable (ie, no variation in proptosis or change in ocular motility measurements for at least 6 months), eye muscle surgery can be planned. Eye muscle surgery should follow orbital decompression because there is a reasonable possibility that decompression will change ocular motility. If there is corneal exposure or unacceptable lid position and proptosis is not an issue, eyelid surgery, at times on both upper and lower lids, can be done. Eyelid surgery should follow eye muscle surgery because a change in eye position, particularly with vertical muscle surgery, can change eyelid position. Finally, the patient should be made aware at the time of diagnosis that there is unlikely to be a return to normal appearance (ie, appearance before the development of thyroid eye disease). PMID:11096765

  19. Complexity and diversity of eyes in early Cambrian ecosystems.

    PubMed

    Zhao, Fangchen; Bottjer, David J; Hu, Shixue; Yin, Zongjun; Zhu, Maoyan

    2013-01-01

    Here we report exceptionally preserved non-biomineralized compound eyes of a non-trilobite arthropod Cindarella eucalla from the lower Cambrian Chengjiang Lagerstätte, China. The specimen represents the oldest microanatomical evidence confirming the occurrence of highly developed vision in the early Cambrian, over 2,000 ommatidia in each eye. Moreover, a quantitative analysis of the distribution of eyes related to life habit, feeding types, and phyla respectively, from the Chengjiang biota indicates that specimens with eyes mostly belong to the arthropods, and they usually were actively mobile epifaunal and nektonic forms as hunters or scavengers. Arthropods took the lead in evolution of 'good vision' and domination in Cambrian communities, which supports the hypothesis that the origin and evolution of 'good vision' was a key trait that promoted preferential diversification and formed the foundation of modern benthic ecosystems in the early Cambrian ocean. PMID:24067397

  20. Complexity and diversity of eyes in Early Cambrian ecosystems

    PubMed Central

    Zhao, Fangchen; Bottjer, David J.; Hu, Shixue; Yin, Zongjun; Zhu, Maoyan

    2013-01-01

    Here we report exceptionally preserved non-biomineralized compound eyes of a non-trilobite arthropod Cindarella eucalla from the lower Cambrian Chengjiang Lagerstätte, China. The specimen represents the oldest microanatomical evidence confirming the occurrence of highly developed vision in the early Cambrian, over 2,000 ommatidia in each eye. Moreover, a quantitative analysis of the distribution of eyes related to life habit, feeding types, and phyla respectively, from the Chengjiang biota indicates that specimens with eyes mostly belong to the arthropods, and they usually were actively mobile epifaunal and nektonic forms as hunters or scavengers. Arthropods took the lead in evolution of ‘good vision' and domination in Cambrian communities, which supports the hypothesis that the origin and evolution of ‘good vision' was a key trait that promoted preferential diversification and formed the foundation of modern benthic ecosystems in the early Cambrian ocean. PMID:24067397

  1. Relationships between sensory stimuli and autonomic nervous regulation during real and virtual exercises

    PubMed Central

    Kiryu, Tohru; Iijima, Atsuhiko; Bando, Takehiko

    2007-01-01

    Background Application of virtual environment (VE) technology to motor rehabilitation increases the number of possible rehabilitation tasks and/or exercises. However, enhancing a specific sensory stimulus sometimes causes unpleasant sensations or fatigue, which would in turn decrease motivation for continuous rehabilitation. To select appropriate tasks and/or exercises for individuals, evaluation of physical activity during recovery is necessary, particularly the changes in the relationship between autonomic nervous activity (ANA) and sensory stimuli. Methods We estimated the ANA from the R-R interval time series of electrocardiogram and incoming sensory stimuli that would activate the ANA. For experiments in real exercise, we measured vehicle data and electromyogram signals during cycling exercise. For experiments in virtual exercise, we measured eye movement in relation to image motion vectors while the subject was viewing a mountain-bike video image from a first-person viewpoint. Results For the real cycling exercise, the results were categorized into four groups by evaluating muscle fatigue in relation to the ANA. They suggested that fatigue should be evaluated on the basis of not only muscle activity but also autonomic nervous regulation after exercise. For the virtual exercise, the ANA-related conditions revealed a remarkable time distribution of trigger points that would change eye movement and evoke unpleasant sensations. Conclusion For expanding the options of motor rehabilitation using VE technology, approaches need to be developed for simultaneously monitoring and separately evaluating the activation of autonomic nervous regulation in relation to neuromuscular and sensory systems with different time scales. PMID:17919339

  2. [The eye and cancer].

    PubMed

    Schalenbourg, Ann; Mantel, Irmela

    2015-12-16

    Cancer involves so rarely the eye that it may be recognized late. The most frequent primary intra-ocular tumours are retinoblastoma in small children and uveal melanoma in adults. Vision loss in systemic cancer has a varied differential diagnosis. Uveal metastases are most often associated with breast cancer, but can herald lung carcinoma. Masquerade syndrome looks like inflammation but represents the ocular involvement of primary CNS non-Hodgkin lymphoma. Systemic cancer drugs, as well as radiotherapy, can cause ocular toxicity, mostly at the retina. In the rare paraneoplastic syndromes, patient's cancer antibodies cross-react with retinal antigens, leading to severe vision loss. When cancer involves the eye, a fast referral into specialized care can significantly improve visual and vital prognosis. PMID:26852556

  3. Sensory development and its relation to habitat change in three species of sciaenids.

    PubMed

    Poling, K R; Fuiman, L A

    1998-01-01

    Visual and mechanosensory development of three sciaenid species was investigated to examine possible correlations between sensory morphology and patterns of habitat use. Although the three species have different migration patterns as early larvae, few differences in sensory morphology occurred between species until late in the larval period. Atlantic croaker, Micropogonias undulatus, were distinguished by enhancements of visual morphology (large eyes, abundant photoreceptors, and best summation of the three species). Croaker arrive inshore later in the larval period and, after settlement, appear to use deeper water habitats than do the other two species. Spotted seatrout, Cynoscion nebulosus, had the fewest enhancements of visual morphology but had more free neuromasts than the other two species late in the larval period. After settlement, seatrout are primarily associated with seagrass habitats. Red drum, Sciaenops ocellatus, did not have pronounced specialization of one sensory system, as did the other two species. For part of the larval period, neuromast numbers were higher in red drum than in the other two species. Later, enhancements of visual morphology did occur, but only eye and lens size were the same as those of Atlantic croaker. Red drum larvae appear to use a wider variety of habitats than do the other two species. In none of the species examined did sensory changes correlate with offshore to inshore movements, and only initial rod formation occurred prior to settlement. Distinct sensory changes did not occur concurrent with habitat changes, probably due to constructional and phylogenetic constraints. Rather, sensory differences are related to the environmental conditions in the predominant inshore habitat occupied by each species after settlement, when morphological limitations are less severe. PMID:9807012

  4. Pioneers of eye movement research

    PubMed Central

    Wade, Nicholas J

    2010-01-01

    Recent advances in the technology affording eye movement recordings carry the risk of neglecting past achievements. Without the assistance of this modern armoury, great strides were made in describing the ways the eyes move. For Aristotle the fundamental features of eye movements were binocular, and he described the combined functions of the eyes. This was later given support using simple procedures like placing a finger over the eyelid of the closed eye and culminated in Hering's law of equal innervation. However, the overriding concern in the 19th century was with eye position rather than eye movements. Appreciating discontinuities of eye movements arose from studies of vertigo. The characteristics of nystagmus were recorded before those of saccades and fixations. Eye movements during reading were described by Hering and by Lamare in 1879; both used similar techniques of listening to sounds made during contractions of the extraocular muscles. Photographic records of eye movements during reading were made by Dodge early in the 20th century, and this stimulated research using a wider array of patterns. In the mid-20th century attention shifted to the stability of the eyes during fixation, with the emphasis on involuntary movements. The contributions of pioneers from Aristotle to Yarbus are outlined. PMID:23396982

  5. Eye preferences in captive chimpanzees

    PubMed Central

    Lambeth, Susan P.; Schapiro, Steven J.

    2013-01-01

    Over the last century, the issue of brain lateralization in primates has been extensively investigated and debated, yet no previous study has reported eye preference in great apes. This study examined eye preference in 45 captive chimpanzees (Pan troglodytes) in response to various stimuli. Eye preference was assessed when animals looked through a hole that only accommodated one eye at an empty box, a mirror, a picture of a dog, a rubber snake, food biscuits, bananas, a rubber duck, and a video camera. Main effects of stimulus type were found for direction of eye preference, number of looks, and looking duration, but not for strength of eye preference. A left-eye bias was found for viewing the rubber snake and a right-eye bias was found for viewing the bananas, supporting theories that emotional valence may affect lateralized behaviors. In addition, a significant shift in eye preference took place from the initial look to subsequent looks when viewing the snake. These results are not consistent with previous reports of human eye preference and may reflect lateralization differences for emotional processing. No relationship between eye preference and previously recorded hand preference was found. PMID:22733385

  6. Schizophrenia and the eye

    PubMed Central

    Silverstein, Steven M.; Rosen, Richard

    2015-01-01

    Although visual processing impairments are common in schizophrenia, it is not clear to what extent these originate in the eye vs. the brain. This review highlights potential contributions, from the retina and other structures of the eye, tovisual processing impairments in schizophrenia and high-risk states. A second goal is to evaluate the status of retinal abnormalities as biomarkers for schizophrenia. The review was motivated by known retinal changes in other disorders (e.g., Parkinson's disease, multiple sclerosis), and their relationships to perceptual and cognitive impairments, and disease progression therein. The evidence reviewed suggests two major conclusions. One is that there are multiple structural and functional disturbances of the eye in schizophrenia, all of which could be factors in the visual disturbances of patients. These include retinal venule widening, retinal nerve fiber layer thinning, dopaminergic abnormalities, abnormal ouput of retinal cells as measured by electroretinography (ERG), maculopathies and retinopathies, cataracts, poor acuity, and strabismus. Some of these are likely to be illness-related, whereas others may be due to medication or comorbid conditions. The second conclusion is that certain retinal findings can serve as biomarkers of neural pathology, and disease progression, in schizophrenia. The strongest evidence for this to date involves findings of widened retinal venules, thinning of the retinal nerve fiber layer, and abnormal ERG amplitudes. These data suggest that a greater understanding of the contribution of retinal and other ocular pathology to the visual and cognitive disturbances of schizophrenia is warranted, and that retinal changes have untapped clinical utility. PMID:26345525

  7. Michelangelo's eye disease.

    PubMed

    Gallenga, P E; Neri, Giampiero; D'Anastasio, Ruggero; Pettorrossi, Vito Enrico; Alfieri, Emilio; Capasso, Luigi

    2012-06-01

    Charged by the Pope Julius II for painting the Cappella Sistina in Rome (between 1508 and 1512), Michelangelo worked in an elevated scaffolding, in an anomalous position with dyes (including poisoning lead salts) and solvents (such as toxic turpentine) dripping on his face and continuously inhaling, in a dim environment illuminated only with oil lamps and candles, as he described himself and sketched in a sonet addressed to Giovanni da Pistoia. In 1510 he began suffering from eye disease: the main symptom was the necessity to elevate the document he was reading up to the level of his eyes. This defect disappeared few months after he finished painting his masterpiece. We hypothesize that the Michelangelo's eyes disease was a form of acquired and transitory nystagmus induced by the many hours he spent in up gaze, with a skew deviation, a form of ocular tilt reaction resulting from the impairment of spatial sensitivity (inversion illusion) due to the persistence of the artist's head in a horizontal position, looking upward. PMID:22425178

  8. Christoph Scheiner's eye studies.

    PubMed

    Daxecker, F

    1992-01-01

    Christoph Scheiner was born in 1573 or 1575. In 1595 he entered into the Order of the Jesuits; he died in 1650. In 1619 his book Oculus, dealing with the optics of the eye, appeared in Innsbruck. The invention of the telescope was of utmost importance for progress in astronomical and physical research. Scheiner himself built telescopes and discovered the sunspots. As a result, an unpleasant priority dispute with Galilei ensued. From 1624 onwards, Scheiner was in Rome, where his main work Rosa Ursina was published in 1630. A part of this book deals with the physiological optics of the eye as well. Some of his discoveries and experiments are taken from these two books: determination of the radius of curvature of the cornea, discovery of the nasal exit of the optic nerve, increase in the radius of curvature of the lens in case of accommodation, Scheiner's procedure (double images with ametropia), refractive indices of various parts of the eye, Scheiner's experiment. Without any doubt, Christoph Scheiner belongs to the foremost scientists of the first half of the 17th century. PMID:1473465

  9. Dominant Epistemologies in Mathematics Education.

    ERIC Educational Resources Information Center

    Triadafillidis, Triadafillos A.

    1998-01-01

    Addresses the relationship between scientism and the dominant epistemologies in the field of mathematics education today. Suggests that the dominance of Cartesianism in mathematics education can be balanced by means of incorporating humanist philosophies. Contains 30 references. (ASK)

  10. The Sensory Neurons of Touch

    PubMed Central

    Abraira, Victoria E.; Ginty, David D.

    2013-01-01

    The somatosensory system decodes a wide range of tactile stimuli and thus endows us with a remarkable capacity for object recognition, texture discrimination, sensory-motor feedback and social exchange. The first step leading to perception of innocuous touch is activation of cutaneous sensory neurons called low-threshold mechanoreceptors (LTMRs). Here, we review the properties and functions of LTMRs, emphasizing the unique tuning properties of LTMR subtypes and the organizational logic of their peripheral and central axonal projections. We discuss the spinal cord neurophysiological representation of complex mechanical forces acting upon the skin and current views of how tactile information is processed and conveyed from the spinal cord to the brain. An integrative model in which ensembles of impulses arising from physiologically distinct LTMRs are integrated and processed in somatotopically aligned mechanosensory columns of the spinal cord dorsal horn underlies the nervous system’s enormous capacity for perceiving the richness of the tactile world. PMID:23972592

  11. Brood care in freshwater crayfish and relationship with the offspring's sensory deficiencies.

    PubMed

    Vogt, Günter; Tolley, Laura

    2004-11-01

    Prolonged brood care is one of the evolutionary clues for the successful colonization of freshwater habitats by freshwater crayfish (Astacida). By means of macrophotography, light microscopy, and scanning electron microscopy we investigated all phases of brood care in freshwater crayfish, with particular emphasis on the morphological structures involved. We selected the recently discovered parthenogenetic marbled crayfish (species identity not yet known) as a model organism due to its fast reproduction and high resistance to handling stress. In order to examine if there is a causal relationship between brood care and the developmental status of the offspring's sensory apparatus, we additionally investigated major sense organs of juvenile Stages 1-5 in comparison with those of the adults. Brood care in the marbled crayfish is characterized by initial and final "active" phases dominated by specific maternal or juvenile behavior and a medial "passive" phase based more on the action of temporarily developed structures rather than on behavior. The most remarkable feature of this period, which includes permanent carrying of the eggs and the first two juvenile stages under the mother's abdomen, is safeguarding of hatching by a telson thread that keeps the helpless newborn hatchlings linked to the egg cases on the maternal pleopods and thus prevents them from being lost. Further important transient structures are the recurved hooks on the first pereiopods of Stage 1 and 2 juveniles that are used to firmly attach these nonfeeding stages to the mother's abdomen. In hatchlings all sense organs necessary for an independent life, such as eyes, olfactory aesthetascs, gustatory fringed setae, hydrodynamic receptor hairs, and statocysts are not developed or are underdeveloped, making brood care indispensable. Most of these sense organs appear in Stage 2 juveniles, but only from Stage 3, the first freelancing and feeding stage, are all sense organs well developed and operating, thus reducing brood care in this final period to temporary provisioning of shelter. Brooding of the eggs and postembryonic brood care are to some extent also found in other freshwater Decapoda like freshwater crabs and aeglid anomurans, but safeguarding of hatching is confined to the Astacida only. This sophisticated mode of passive brood care is unique in the animal kingdom and is apparently related to the sensory deficiencies of the first juvenile stage. PMID:15376277

  12. Peripheral myopization using a dominant design multifocal contact lens

    PubMed Central

    Lopes-Ferreira, Daniela; Ribeiro, Cláudia; Maia, Raquel; García-Porta, Nery; Queirós, António; Villa-Collar, César; González-Méijome, José Manuel

    2011-01-01

    Purpose The purpose of this study was to characterize the central and peripheral refraction across the horizontal meridian of the visual field without and with a multifocal dominant design soft contact lens of different add powers (+1.00 D to +4.00 D) in emmetropic eyes. Methods Twenty right eyes from 20 emmetropic patients (mean spherical equivalent central refraction –0.06 ± 0.54 D) with a mean age of 21.6 ± 2.3 years were fitted with Proclear Multifocal dominant design (Coopervision, Pleasanton, CA, USA). Lenses had add powers from +1.00 to +4.00 D in 1.00 D steps. The central and peripheral refraction was measured along the horizontal meridian up to 35° of eccentricity in the nasal and temporal retinal area in 5° steps using a open-field autorefractometer. Results Only the +3.00 and +4.00 D add powers generated a significant change in the peripheral refractive pattern compared to central refraction and compared with the no-lens wearing situation. The average myopic increase with these lenses was –3.00 D and –5.00 (p < 0.001) at the margins of inspected nasal and temporal visual field, respectively. Conclusions Multifocal dominant design soft contact lenses are able to change the peripheral refractive profile in emmetropic eyes increasing relative peripheral myopia. Lenses with +3.00 D add power seem to be the best option to create such effect due to significant peripheral myopization.

  13. Validity of Sensory Systems as Distinct Constructs

    PubMed Central

    Su, Chia-Ting

    2014-01-01

    This study investigated the validity of sensory systems as distinct measurable constructs as part of a larger project examining Ayres’s theory of sensory integration. Confirmatory factor analysis (CFA) was conducted to test whether sensory questionnaire items represent distinct sensory system constructs. Data were obtained from clinical records of two age groups, 2- to 5-yr-olds (n = 231) and 6- to 10-yr-olds (n = 223). With each group, we tested several CFA models for goodness of fit with the data. The accepted model was identical for each group and indicated that tactile, vestibular–proprioceptive, visual, and auditory systems form distinct, valid factors that are not age dependent. In contrast, alternative models that grouped items according to sensory processing problems (e.g., over- or underresponsiveness within or across sensory systems) did not yield valid factors. Results indicate that distinct sensory system constructs can be measured validly using questionnaire data. PMID:25184467

  14. Sensory impacts of food-packaging interactions.

    PubMed

    Duncan, Susan E; Webster, Janet B

    2009-01-01

    Sensory changes in food products result from intentional or unintentional interactions with packaging materials and from failure of materials to protect product integrity or quality. Resolving sensory issues related to plastic food packaging involves knowledge provided by sensory scientists, materials scientists, packaging manufacturers, food processors, and consumers. Effective communication among scientists and engineers from different disciplines and industries can help scientists understand package-product interactions. Very limited published literature describes sensory perceptions associated with food-package interactions. This article discusses sensory impacts, with emphasis on oxidation reactions, associated with the interaction of food and materials, including taints, scalping, changes in food quality as a function of packaging, and examples of material innovations for smart packaging that can improve sensory quality of foods and beverages. Sensory evaluation is an important tool for improved package selection and development of new materials. PMID:19389606

  15. Sensory Augmentation for the Blind

    PubMed Central

    Kärcher, Silke M.; Fenzlaff, Sandra; Hartmann, Daniela; Nagel, Saskia K.; König, Peter

    2012-01-01

    Common navigational aids used by blind travelers during large-scale navigation divert attention away from important cues of the immediate environment (i.e., approaching vehicles). Sensory augmentation devices, relying on principles similar to those at work in sensory substitution, can potentially bypass the bottleneck of attention through sub-cognitive implementation of a set of rules coupling motor actions with sensory stimulation. We provide a late blind subject with a vibrotactile belt that continually signals the direction of magnetic north. The subject completed a set of behavioral tests before and after an extended training period. The tests were complemented by questionnaires and interviews. This newly supplied information improved performance on different time scales. In a pointing task we demonstrate an instant improvement of performance based on the signal provided by the device. Furthermore, the signal was helpful in relevant daily tasks, often complicated for the blind, such as keeping a direction over longer distances or taking shortcuts in familiar environments. A homing task with an additional attentional load demonstrated a significant improvement after training. The subject found the directional information highly expedient for the adjustment of his inner maps of familiar environments and describes an increase in his feeling of security when exploring unfamiliar environments with the belt. The results give evidence for a firm integration of the newly supplied signals into the behavior of this late blind subject with better navigational performance and more courageous behavior in unfamiliar environments. Most importantly, the complementary information provided by the belt lead to a positive emotional impact with enhanced feeling of security. The present experimental approach demonstrates the positive potential of sensory augmentation devices for the help of handicapped people. PMID:22403535

  16. Development of Metallic Sensory Alloys

    NASA Technical Reports Server (NTRS)

    Wallace Terryl A.; Newman, John A.; Horne, Michael R.; Messick, Peter L.

    2010-01-01

    Existing nondestructive evaluation (NDE) technologies are inherently limited by the physical response of the structural material being inspected and are therefore not generally effective at the identification of small discontinuities, making the detection of incipient damage extremely difficult. One innovative solution to this problem is to enhance or complement the NDE signature of structural materials to dramatically improve the ability of existing NDE tools to detect damage. To address this need, a multifunctional metallic material has been developed that can be used in structural applications. The material is processed to contain second phase sensory particles that significantly improve the NDE response, enhancing the ability of conventional NDE techniques to detect incipient damage both during and after flight. Ferromagnetic shape-memory alloys (FSMAs) are an ideal material for these sensory particles as they undergo a uniform and repeatable change in both magnetic properties and crystallographic structure (martensitic transformation) when subjected to strain and/or temperature changes which can be detected using conventional NDE techniques. In this study, the use of a ferromagnetic shape memory alloy (FSMA) as the sensory particles was investigated.

  17. Dominant optic atrophy

    PubMed Central

    2012-01-01

    Definition of the disease Dominant Optic Atrophy (DOA) is a neuro-ophthalmic condition characterized by a bilateral degeneration of the optic nerves, causing insidious visual loss, typically starting during the first decade of life. The disease affects primary the retinal ganglion cells (RGC) and their axons forming the optic nerve, which transfer the visual information from the photoreceptors to the lateral geniculus in the brain. Epidemiology The prevalence of the disease varies from 1/10000 in Denmark due to a founder effect, to 1/30000 in the rest of the world. Clinical description DOA patients usually suffer of moderate visual loss, associated with central or paracentral visual field deficits and color vision defects. The severity of the disease is highly variable, the visual acuity ranging from normal to legal blindness. The ophthalmic examination discloses on fundoscopy isolated optic disc pallor or atrophy, related to the RGC death. About 20% of DOA patients harbour extraocular multi-systemic features, including neurosensory hearing loss, or less commonly chronic progressive external ophthalmoplegia, myopathy, peripheral neuropathy, multiple sclerosis-like illness, spastic paraplegia or cataracts. Aetiology Two genes (OPA1, OPA3) encoding inner mitochondrial membrane proteins and three loci (OPA4, OPA5, OPA8) are currently known for DOA. Additional loci and genes (OPA2, OPA6 and OPA7) are responsible for X-linked or recessive optic atrophy. All OPA genes yet identified encode mitochondrial proteins embedded in the inner membrane and ubiquitously expressed, as are the proteins mutated in the Leber Hereditary Optic Neuropathy. OPA1 mutations affect mitochondrial fusion, energy metabolism, control of apoptosis, calcium clearance and maintenance of mitochondrial genome integrity. OPA3 mutations only affect the energy metabolism and the control of apoptosis. Diagnosis Patients are usually diagnosed during their early childhood, because of bilateral, mild, otherwise unexplained visual loss related to optic discs pallor or atrophy, and typically occurring in the context of a family history of DOA. Optical Coherence Tomography further discloses non-specific thinning of retinal nerve fiber layer, but a normal morphology of the photoreceptors layers. Abnormal visual evoked potentials and pattern ERG may also reflect the dysfunction of the RGCs and their axons. Molecular diagnosis is provided by the identification of a mutation in the OPA1 gene (75% of DOA patients) or in the OPA3 gene (1% of patients). Prognosis Visual loss in DOA may progress during puberty until adulthood, with very slow subsequent chronic progression in most of the cases. On the opposite, in DOA patients with associated extra-ocular features, the visual loss may be more severe over time. Management To date, there is no preventative or curative treatment in DOA; severely visually impaired patients may benefit from low vision aids. Genetic counseling is commonly offered and patients are advised to avoid alcohol and tobacco consumption, as well as the use of medications that may interfere with mitochondrial metabolism. Gene and pharmacological therapies for DOA are currently under investigation. PMID:22776096

  18. Meis1 coordinates a network of genes implicated in eye development and microphthalmia.

    PubMed

    Marcos, Séverine; González-Lázaro, Monica; Beccari, Leonardo; Carramolino, Laura; Martin-Bermejo, Maria Jesus; Amarie, Oana; Mateos-San Martín, Daniel; Torroja, Carlos; Bogdanovi?, Ozren; Doohan, Roisin; Puk, Oliver; Hrab? de Angelis, Martin; Graw, Jochen; Gomez-Skarmeta, Jose Luis; Casares, Fernando; Torres, Miguel; Bovolenta, Paola

    2015-09-01

    Microphthalmos is a rare congenital anomaly characterized by reduced eye size and visual deficits of variable degree. Sporadic and hereditary microphthalmos have been associated with heterozygous mutations in genes fundamental for eye development. Yet, many cases are idiopathic or await the identification of molecular causes. Here we show that haploinsufficiency of Meis1, which encodes a transcription factor with evolutionarily conserved expression in the embryonic trunk, brain and sensory organs, including the eye, causes microphthalmic traits and visual impairment in adult mice. By combining analysis of Meis1 loss-of-function and conditional Meis1 functional rescue with ChIP-seq and RNA-seq approaches we show that, in contrast to its preferential association with Hox-Pbx BSs in the trunk, Meis1 binds to Hox/Pbx-independent sites during optic cup development. In the eye primordium, Meis1 coordinates, in a dose-dependent manner, retinal proliferation and differentiation by regulating genes responsible for human microphthalmia and components of the Notch signaling pathway. In addition, Meis1 is required for eye patterning by controlling a set of eye territory-specific transcription factors, so that in Meis1(-/-) embryos boundaries among the different eye territories are shifted or blurred. We propose that Meis1 is at the core of a genetic network implicated in eye patterning/microphthalmia, and represents an additional candidate for syndromic cases of these ocular malformations. PMID:26253404

  19. Computing vector differences using a gain field-like mechanism in monkey frontal eye field

    PubMed Central

    Cassanello, Carlos R; Ferrera, Vincent P

    2007-01-01

    Signals related to eye position are essential for visual perception and eye movements, and are powerful modulators of sensory responses in many regions of the visual and oculomotor systems. We show that visual and pre-saccadic responses of frontal eye field (FEF) neurons are modulated by initial eye position in a way suggestive of a multiplicative mechanism (gain field). Furthermore the slope of the eye position sensitivity tends to be negatively correlated with preferred retinal position across the population. A model with Gaussian visual receptive fields and linear-rectified eye position gain fields accounts for a large portion of the variance in the recorded data. Using physiologically derived parameters, this model is able to subtract the gaze shift from the vector representing the retinal location of the target. This computation might be used to maintain a memory of target location in space during ongoing eye movements. This updated spatial memory can be read directly from the locus of the peak of activity across the retinotopic map of FEF and it is the result of a vector subtraction between retinal target location when flashed and subsequent eye displacement in the dark. PMID:17510192

  20. Connecting ears to eye muscles: evolution of a 'simple' reflex arc.

    PubMed

    Straka, Hans; Fritzsch, Bernd; Glover, Joel C

    2014-01-01

    Developmental and evolutionary data from vertebrates are beginning to elucidate the origin of the sensorimotor pathway that links gravity and motion detection to image-stabilizing eye movements--the vestibulo-ocular reflex (VOR). Conserved transcription factors coordinate the development of the vertebrate ear into three functional sensory compartments (graviception/translational linear acceleration, angular acceleration and sound perception). These sensory components connect to specific populations of vestibular and auditory projection neurons in the dorsal hindbrain through undetermined molecular mechanisms. In contrast, a molecular basis for the patterning of the vestibular projection neurons is beginning to emerge. These are organized through the actions of rostrocaudally and dorsoventrally restricted transcription factors into a 'hodological mosaic' within which coherent and largely segregated subgroups are specified to project to different targets in the spinal cord and brain stem. A specific set of these regionally diverse vestibular projection neurons functions as the central element that transforms vestibular sensory signals generated by active and passive head and body movements into motor output through the extraocular muscles. The large dynamic range of motion-related sensory signals requires an organization of VOR pathways as parallel, frequency-tuned, hierarchical connections from the sensory periphery to the motor output. We suggest that eyes, ears and functional connections subserving the VOR are vertebrate novelties that evolved into a functionally coherent motor control system in an almost stereotypic organization across vertebrate taxa. PMID:24776996

  1. Visual Experience Is Required for the Development of Eye Movement Maps in the Mouse Superior Colliculus

    PubMed Central

    Wang, Lupeng; Liu, Mingna

    2015-01-01

    Topographic maps are a fundamental feature of the brain's representations of the sensory environment as well as an efficient way to organize motor control networks. Although great progress has been made in our understanding of sensory map development, very little is known about how topographic representations for motor control develop and interface with sensory maps. Here we map the representation for eye movements in the superior colliculus (SC) in awake mice. As stimulation sites were sampled along the anterior–posterior axis, small amplitude, nasally directed (ipsiversive) saccadic eye movements were evoked by microstimulation in anterior SC, followed by a smooth progression to large, temporally directed (contraversive) movements in posterior SC. This progressive change of movement amplitude and direction is consistent with the global polarity of the retinotopic map in the superficial SC, just as in primates and cats. We then investigated the role of visual experience in the development of eye movement map by studying mice reared in complete darkness. Saccades evoked by SC stimulation as well as spontaneous saccadic eye movements were larger in the dark-reared mice, indicating that visual experience is required to fine-tune the gain of saccades and to establish normal eye movement maps in the SC. Our experiments provide a foundation for future studies to investigate the synaptic organization and developmental mechanisms of sensorimotor transformations in mice. SIGNIFICANCE STATEMENT The superior colliculus (SC) is a midbrain structure important for multisensory integration and sensorimotor transformation. Here we have studied eye movement representations in the SC of mice, a species that has become a popular model in vision research because of available genetic tools. Our studies show mice make saccadic eye movements spontaneously and in response to SC stimulation. The mouse SC contains an eye movement map that has the same global polarity as the overlaying visual map, just like in cats and primates. Furthermore, we show that visual experience is required for establishing the normal eye movement map. Our study provides a necessary basis for future mechanistic studies of how SC motor maps develop and become aligned with sensory maps. PMID:26338338

  2. Effects of aging on eye movements in the real world

    PubMed Central

    Dowiasch, Stefan; Marx, Svenja; Einhäuser, Wolfgang; Bremmer, Frank

    2015-01-01

    The effects of aging on eye movements are well studied in the laboratory. Increased saccade latencies or decreased smooth-pursuit gain are well established findings. The question remains whether these findings are influenced by the rather untypical environment of a laboratory; that is, whether or not they transfer to the real world. We measured 34 healthy participants between the age of 25 and 85 during two everyday tasks in the real world: (I) walking down a hallway with free gaze, (II) visual tracking of an earth-fixed object while walking straight-ahead. Eye movements were recorded with a mobile light-weight eye tracker, the EyeSeeCam (ESC). We find that age significantly influences saccade parameters. With increasing age, saccade frequency, amplitude, peak velocity, and mean velocity are reduced and the velocity/amplitude distribution as well as the velocity profile become less skewed. In contrast to laboratory results on smooth pursuit, we did not find a significant effect of age on tracking eye-movements in the real world. Taken together, age-related eye-movement changes as measured in the laboratory only partly resemble those in the real world. It is well-conceivable that in the real world additional sensory cues, such as head-movement or vestibular signals, may partially compensate for age-related effects, which, according to this view, would be specific to early motion processing. In any case, our results highlight the importance of validity for natural situations when studying the impact of aging on real-life performance. PMID:25713524

  3. Effects of aging on eye movements in the real world.

    PubMed

    Dowiasch, Stefan; Marx, Svenja; Einhäuser, Wolfgang; Bremmer, Frank

    2015-01-01

    The effects of aging on eye movements are well studied in the laboratory. Increased saccade latencies or decreased smooth-pursuit gain are well established findings. The question remains whether these findings are influenced by the rather untypical environment of a laboratory; that is, whether or not they transfer to the real world. We measured 34 healthy participants between the age of 25 and 85 during two everyday tasks in the real world: (I) walking down a hallway with free gaze, (II) visual tracking of an earth-fixed object while walking straight-ahead. Eye movements were recorded with a mobile light-weight eye tracker, the EyeSeeCam (ESC). We find that age significantly influences saccade parameters. With increasing age, saccade frequency, amplitude, peak velocity, and mean velocity are reduced and the velocity/amplitude distribution as well as the velocity profile become less skewed. In contrast to laboratory results on smooth pursuit, we did not find a significant effect of age on tracking eye-movements in the real world. Taken together, age-related eye-movement changes as measured in the laboratory only partly resemble those in the real world. It is well-conceivable that in the real world additional sensory cues, such as head-movement or vestibular signals, may partially compensate for age-related effects, which, according to this view, would be specific to early motion processing. In any case, our results highlight the importance of validity for natural situations when studying the impact of aging on real-life performance. PMID:25713524

  4. From cornea to retinal image in invertebrate eyes.

    PubMed

    Nilsson, D E

    1990-02-01

    The optical information processing that takes place in an eye involves a large variety of very different optical components that are put together to solve a task which, in its basic nature, does not differ much from one species to another. The principal task of an eye is to sort the incoming photons so that they excite specific sensory neurons depending on angle of incidence, wavelength and plane of polarization. Despite the apparent simplicity of the task, the solutions to it are often complex and the variation between species is enormous. The pinhole camera, the Keplerian and Galilean telescopes, the corner reflector, optical fibres, and interference filters, are all names of optical devices invented by man. It now appears that all of these devices, and many more, exist in various combinations in the optics of invertebrate eyes. The similarity between man's and nature's optical engineering has been useful in many ways. For the study of eyes, it has helped to understand biological design principles in unparalleled detail. PMID:1690931

  5. Bidirectional Ocular Dominance Plasticity of Inhibitory Networks: Recent Advances and Unresolved Questions

    PubMed Central

    Smith, Gordon B.; Bear, Mark F.

    2010-01-01

    Monocular visual deprivation (MD) produces profound changes in the ocular dominance (OD) of neurons in the visual cortex. MD shifts visually evoked responses away from the deprived eye and toward domination by the open-eye. Over 30 years ago, two different theories were proposed to account for these changes: either through effects on excitatory visual drive, thereby shifting the balance of excitation in favor of the open-eye, or through effects on intracortical inhibition, thereby suppressing responses from the deprived eye. In the intervening years, a scientific consensus emerged that the major functional effects of MD result from plasticity at excitatory connections in the visual cortex. A recent study by Yazaki-Sugiyama et al. (2009) in mouse visual cortex appears to re-open the debate. Here we take a critical look at these intriguing new data in the context of other recent findings in rodent visual cortex. PMID:20592959

  6. Noise-enhanced target discrimination under the influence of fixational eye movements and external noise

    NASA Astrophysics Data System (ADS)

    Starzynski, Christian; Engbert, Ralf

    2009-03-01

    Active motor processes are present in many sensory systems to enhance perception. In the human visual system, miniature eye movements are produced involuntarily and unconsciously when we fixate a stationary target. These fixational eye movements represent self-generated noise which serves important perceptual functions. Here we investigate fixational eye movements under the influence of external noise. In a two-choice discrimination task, the target stimulus performed a random walk with varying noise intensity. We observe noise-enhanced discrimination of the target stimulus characterized by a U-shaped curve of manual response times as a function of the diffusion constant of the stimulus. Based on the experiments, we develop a stochastic information-accumulator model for stimulus discrimination in a noisy environment. Our results provide a new explanation for the constructive role of fixational eye movements in visual perception.

  7. The cortex is in overall control of ‘voluntary' eye movement

    PubMed Central

    Pouget, P

    2015-01-01

    The neural circuits that control eye movements are complex and distributed in brainstem, basal ganglia, cerebellum, and multiple areas of cortex. The anatomical function of the substrates implicated in eye movements has been studied for decades in numerous countries, laboratories, and clinics. The modest goal of this brief review is twofold. (1) To present a focused overview of the knowledge about the role of the cerebral cortex in voluntary control of eye movements. (2) To very briefly mention two findings showing that the accepted hierarchy between the frontal and the occipital sensory areas involved in sensory–motor transformation might not be so trivial to reconcile, and to interpret in the context of eye movement command. This presentation has been part of the 44th Cambridge Ophthalmological Symposium, on ocular motility, 3 September 2014 to 5 November 2014. PMID:25475239

  8. Sensory population decoding for visually-guided movements

    PubMed Central

    Hohl, Sonja S.; Chaisanguanthum, Kris S.; Lisberger, Stephen G.

    2013-01-01

    We have used a new approach to study the neural decoding function that converts the population response in extrastriate area MT into estimates of target motion to drive smooth pursuit eye movement. Experiments reveal significant trial-by-trial correlations between the responses of MT neurons and the initiation of pursuit. The preponderance of significant correlations and the relatively low reduction in noise between MT and the behavioral output support the hypothesis of a sensory origin for at least some of the trial-by-trial variation in pursuit initiation. The finding of mainly positive MT-pursuit correlations, whether the target speed is faster or slower than the neuron’s preferred speed, places strong constraints on the neural decoding computation. We propose that decoding is based on normalizing a weighted population vector of opponent motion responses; normalization comes from neurons uncorrelated with those used to compute the weighted population vector. PMID:23849202

  9. Eyes on the Universe

    NASA Astrophysics Data System (ADS)

    Moore, Patrick

    Eyes on the Universe is an illustrated history of the telescope, beginning with pre-telescopic observatories and the refractors of Galileo, Lippershey and Digges, and ending with the most modern instruments including - of course - the Hubble Space Telescope. Written by Dr Patrick Moore CBE, to celebrate the 40th Anniversary of the world's longest-running television programme, the BBC's The Sky at Night, the book takes an enthusiastic look at the development of astronomical telescopes. It provides its readers with a fascinating overview of the way astronomical telescopes have evolved with technology during the past 450 years. Amateur and professional astronomers alike will find this book both entertaining and instructive.

  10. [Eye and the environment].

    PubMed

    Voide, Nathalie; Kaeser, Pierre-François; Behar-Cohen, Francine

    2015-12-16

    The eyes are exposed to multiple environmental factors, which affect visual development, comfort, and visual health. While overexposure to sunlight can cause ocular surface and retinal pathologies, insufficient exposure to daylight could significantly contribute to myopia progression. New artificial lights, namely LED, have a higher risk of retinal phototoxicity, and could alter ocular circadian rhythm. The significant increase of prevalence of ocular allergies could be caused by the proliferation of environmental polluting substances, like tobacco smoke, fuel combustion by-products, or phtalates, which are found in many types of plastics. Finally, some dietary supplements could play a protective role in certain types of ocular pathologies, namely retinal pathologies. PMID:26852551

  11. Lens of Eye Dosimetry

    SciTech Connect

    Mallett, Michael Wesley

    2015-03-23

    An analysis of LANL occupational dose measurements was made with respect to lens of eye dose (LOE), in particular, for plutonium workers. Table 1 shows the reported LOE as a ratio of the “deep” (photon only) and “deep+neutron” dose for routine monitored workers at LANL for the past ten years. The data compares the mean and range of these values for plutonium workers* and non-routine plutonium workers. All doses were reported based on measurements with the LANL Model 8823 TLD.

  12. Rapid eye movement sleep promotes cortical plasticity in the developing brain

    PubMed Central

    Dumoulin Bridi, Michelle C.; Aton, Sara J.; Seibt, Julie; Renouard, Leslie; Coleman, Tammi; Frank, Marcos G.

    2015-01-01

    Rapid eye movement sleep is maximal during early life, but its function in the developing brain is unknown. We investigated the role of rapid eye movement sleep in a canonical model of developmental plasticity in vivo (ocular dominance plasticity in the cat) induced by monocular deprivation. Preventing rapid eye movement sleep after monocular deprivation reduced ocular dominance plasticity and inhibited activation of a kinase critical for this plasticity (extracellular signal–regulated kinase). Chronic single-neuron recording in freely behaving cats further revealed that cortical activity during rapid eye movement sleep resembled activity present during monocular deprivation. This corresponded to times of maximal extracellular signal–regulated kinase activation. These findings indicate that rapid eye movement sleep promotes molecular and network adaptations that consolidate waking experience in the developing brain. PMID:26601213

  13. Somnolence, akinesia, and sensory activation of motivated behavior in the lateral hypothalamic syndrome.

    PubMed Central

    Levitt, D R; Teitelbaum, P

    1975-01-01

    After lateral hypothalamic damage in rats, somnolence, akinesia, and sensory neglect combine to produce complete aphagia. Only simple automatisms (such as grooming, chewing, licking) are present, but intense stimuli can activate more complex actions (walking, orientation, swimming). In the anorexic stage, tactile stimuli dominate in steering locomotion and "spontaneous" locomotion depends on activation from the empty stomach. Images PMID:1101268

  14. Testing sensory evidence against mnemonic templates

    PubMed Central

    Myers, Nicholas E; Rohenkohl, Gustavo; Wyart, Valentin; Woolrich, Mark W; Nobre, Anna C; Stokes, Mark G

    2015-01-01

    Most perceptual decisions require comparisons between current input and an internal template. Classic studies propose that templates are encoded in sustained activity of sensory neurons. However, stimulus encoding is itself dynamic, tracing a complex trajectory through activity space. Which part of this trajectory is pre-activated to reflect the template? Here we recorded magneto- and electroencephalography during a visual target-detection task, and used pattern analyses to decode template, stimulus, and decision-variable representation. Our findings ran counter to the dominant model of sustained pre-activation. Instead, template information emerged transiently around stimulus onset and quickly subsided. Cross-generalization between stimulus and template coding, indicating a shared neural representation, occurred only briefly. Our results are compatible with the proposal that template representation relies on a matched filter, transforming input into task-appropriate output. This proposal was consistent with a signed difference response at the perceptual decision stage, which can be explained by a simple neural model. DOI: http://dx.doi.org/10.7554/eLife.09000.001 PMID:26653854

  15. Aging and dry eye disease

    PubMed Central

    Ding, Juan; Sullivan, David A.

    2012-01-01

    Dry eye disease is a prevalent eye disorder that in particular affects the elderly population. One of the major causes of dry eye, meibomian gland dysfunction (MGD), shows increased prevalence with aging. MGD is caused by hyperkeratinization of the ductal epithelium of meibomian gland and reduced quantity and/or quality of meibum, the holocrine product that stabilizes and prevents the evaporation of the tear film. Of note, retinoids which are used in current anti-aging cosmetics may promote the development of MGD and dry eye disease. In this review, we will discuss the possible mechanisms of age-related MGD. PMID:22569356

  16. Recognizing and Treating Eye Injuries

    MedlinePLUS

    ... Uveitis Focus On Pediatric Ophthalmology Education Center Oculofacial Plastic Surgery Center Laser Surgery Education Center Redmond Ethics Center Global Ophthalmology Guide Academy Publications EyeNet Ophthalmology ...

  17. Childhood Eye Diseases and Conditions

    MedlinePLUS

    ... Uveitis Focus On Pediatric Ophthalmology Education Center Oculofacial Plastic Surgery Center Laser Surgery Education Center Redmond Ethics Center Global Ophthalmology Guide Academy Publications EyeNet Ophthalmology ...

  18. Obesity and Eye Diseases

    PubMed Central

    Cheung, Ning; Wong, Tien Y.

    2009-01-01

    The prevalence of obesity has reached epidemic proportions in many countries. While its impact on overall health is well documented, less is known about the ocular manifestations of obesity. Amongst different eye diseases, obesity has been linked with age-related cataract, glaucoma, age-related maculopathy, and diabetic retinopathy. Numerous population-based and prospective studies support an association between obesity and risk of age-related cataract. However, the nature and strength of these associations, particularly with the different cataract subtypes, remains to be determined. There is strong evidence that obesity is associated with elevated intraocular pressure, but there is no convincing data to support a more direct association between obesity and glaucomatous optic neuropathy. Studies to date have not found a consistent pattern of association between obesity and risk of age-related maculopathy or diabetic retinopathy. Thus, while obesity may be a risk factor for many ocular conditions, the present literature is inadequate to establish any convincing associations. Furthermore, whether weight loss reduces the risk of eye diseases remains unresolved. Because of the potential public health impact of obesity, there is a greater need to understand its ocular effects. PMID:17355856

  19. Eye Surgery Light

    NASA Technical Reports Server (NTRS)

    1978-01-01

    During eye surgery, the surgeon uses an illuminating instrument called an opthalmoscope for close examination of the retina or the interior of the eye. Ordinarily, electric power for the head-mounted light is supplied through a cord from an overhead swivel arm or a floor pedestal. Within limits of cord length and swivel arm movement, the surgeon has considerable freedom of motion. But when more than one opthalmoscope is involved, tangling and interference of the power cords becomes a problem. St. Luke's Hospital, Cleveland, Ohio asked Lewis Research Center for assistance in finding a solution. Lewis responded with a battery-powered system that totally frees the surgeon of attached cords and swivels. Borrowing from space technology, Lewis used small, lightweight nickel-cadmium batteries that can deliver high intensity light for an hour and can be recharged overnight. The Opthalmoscope Powerpack consists of eight batteries in three containers affixed to a webbed belt, and a novel on-off switch equipped with a springloaded plexiglass "flapper." The belt pack is worn underneath the surgical gown and the flapper permits the doctor to activate the switch by elbow pressure. Lewis built five units and they have been in service at St. Luke's Hospital for a year. Used for routine examinations as well as for surgery, they have demonstrated excellent reliability.

  20. Eye Surgery Light

    NASA Technical Reports Server (NTRS)

    1978-01-01

    During eye surgery, the surgeon uses an illuminating instrument called an opthalmoscope for close examination of the retina or the interior of the eye. Ordinarily, electric power for the head-mounted light is supplied through a cord from an overhead swivel arm or a floor pedestal. Within limits of cord length and swivel arm movement, the surgeon has considerable freedom of motion. But when more than one opthalmoscope is involved, tangling and interference of the power cords becomes a problem. St. Luke's Hospital, Cleveland, Ohio asked Lewis Research Center for assistance in finding a solution. Lewis responded with a battery-powered system that totally frees the surgeon of attached cords and swivels. Borrowing from space technology, Lewis used small, lightweight nickel-cadmium batteries that can deliver high intensity light for an hour and can be recharged overnight. The Opthalmoscope Powerpack consists of eight batteries in three containers affixed to a webbed belt, and a novel on-off switch equipped with a spring-loaded plexiglass 'flapper.' The belt pack is worn underneath the surgical gown and the flapper permits the doctor to activate the switch by elbow pressure. Lewis built five units and they have been in service at St. Luke's Hospital for a year. Used for routine examinations as well as for surgery, they have demonstrated excellent reliability.

  1. Cognitive mechanisms associated with auditory sensory gating.

    PubMed

    Jones, L A; Hills, P J; Dick, K M; Jones, S P; Bright, P

    2016-02-01

    Sensory gating is a neurophysiological measure of inhibition that is characterised by a reduction in the P50 event-related potential to a repeated identical stimulus. The objective of this work was to determine the cognitive mechanisms that relate to the neurological phenomenon of auditory sensory gating. Sixty participants underwent a battery of 10 cognitive tasks, including qualitatively different measures of attentional inhibition, working memory, and fluid intelligence. Participants additionally completed a paired-stimulus paradigm as a measure of auditory sensory gating. A correlational analysis revealed that several tasks correlated significantly with sensory gating. However once fluid intelligence and working memory were accounted for, only a measure of latent inhibition and accuracy scores on the continuous performance task showed significant sensitivity to sensory gating. We conclude that sensory gating reflects the identification of goal-irrelevant information at the encoding (input) stage and the subsequent ability to selectively attend to goal-relevant information based on that previous identification. PMID:26716891

  2. Cognitive mechanisms associated with auditory sensory gating

    PubMed Central

    Jones, L.A.; Hills, P.J.; Dick, K.M.; Jones, S.P.; Bright, P.

    2016-01-01

    Sensory gating is a neurophysiological measure of inhibition that is characterised by a reduction in the P50 event-related potential to a repeated identical stimulus. The objective of this work was to determine the cognitive mechanisms that relate to the neurological phenomenon of auditory sensory gating. Sixty participants underwent a battery of 10 cognitive tasks, including qualitatively different measures of attentional inhibition, working memory, and fluid intelligence. Participants additionally completed a paired-stimulus paradigm as a measure of auditory sensory gating. A correlational analysis revealed that several tasks correlated significantly with sensory gating. However once fluid intelligence and working memory were accounted for, only a measure of latent inhibition and accuracy scores on the continuous performance task showed significant sensitivity to sensory gating. We conclude that sensory gating reflects the identification of goal-irrelevant information at the encoding (input) stage and the subsequent ability to selectively attend to goal-relevant information based on that previous identification. PMID:26716891

  3. The amblyopic eye in subjects with anisometropia show increased saccadic latency in the delayed saccade task

    PubMed Central

    Perdziak, Maciej; Witkowska, Dagmara; Gryncewicz, Wojciech; Przekoracka-Krawczyk, Anna; Ober, Jan

    2014-01-01

    The term amblyopia is used to describe reduced visual function in one eye (or both eyes, though not so often) which cannot be fully improved by refractive correction and explained by the organic cause observed during regular eye examination. Amblyopia is associated with abnormal visual experience (e.g., anisometropia) during infancy or early childhood. Several studies have shown prolongation of saccadic latency time in amblyopic eye. In our opinion, study of saccadic latency in the context of central vision deficits assessment, should be based on central retina stimulation. For this reason, we proposed saccade delayed task. It requires inhibitory processing for maintaining fixation on the central target until it disappears—what constitutes the GO signal for saccade. The experiment consisted of 100 trials for each eye and was performed under two viewing conditions: monocular amblyopic/non-dominant eye and monocular dominant eye. We examined saccadic latency in 16 subjects (mean age 30 ± 11 years) with anisometropic amblyopia (two subjects had also microtropia) and in 17 control subjects (mean age 28 ± 8 years). Participants were instructed to look at central (fixation) target and when it disappears, to make the saccade toward the periphery (10°) as fast as possible, either left or the right target. The study results have proved the significant difference in saccadic latency between the amblyopic (mean 262 ± 48 ms) and dominant (mean 237 ± 45 ms) eye, in anisometropic group. In the control group, the saccadic latency for dominant (mean 226 ± 32 ms) and non-dominant (mean 230 ± 29 ms) eye was not significantly different. By the use of LATER (Linear Approach to the Threshold with Ergodic Rate) decision model we interpret our findings as a decrease in accumulation of visual information acquired by means of central retina in subjects with anisometropic amblyopia. PMID:25352790

  4. Sensory Motor Coordination in Robonaut

    NASA Technical Reports Server (NTRS)

    Peters, Richard Alan, II

    2003-01-01

    As a participant of the year 2000 NASA Summer Faculty Fellowship Program, I worked with the engineers of the Dexterous Robotics Laboratory at NASA Johnson Space Center on the Robonaut project. The Robonaut is an articulated torso with two dexterous arms, left and right five-fingered hands, and a head with cameras mounted on an articulated neck. This advanced space robot, now driven only teleoperatively using VR gloves, sensors and helmets, is to be upgraded to a thinking system that can find, interact with and assist humans autonomously, allowing the Crew to work with Robonaut as a (junior) member of their team. Thus, the work performed this summer was toward the goal of enabling Robonaut to operate autonomously as an intelligent assistant to astronauts. Our underlying hypothesis is that a robot can develop intelligence if it learns a set of basic behaviors (i.e., reflexes - actions tightly coupled to sensing) and through experience learns how to sequence these to solve problems or to accomplish higher-level tasks. We describe our approach to the automatic acquisition of basic behaviors as learning sensory-motor coordination (SMC). Although research in the ontogenesis of animals development from the time of conception) supports the approach of learning SMC as the foundation for intelligent, autonomous behavior, we do not know whether it will prove viable for the development of autonomy in robots. The first step in testing the hypothesis is to determine if SMC can be learned by the robot. To do this, we have taken advantage of Robonaut's teleoperated control system. When a person teleoperates Robonaut, the person's own SMC causes the robot to act purposefully. If the sensory signals that the robot detects during teleoperation are recorded over several repetitions of the same task, it should be possible through signal analysis to identify the sensory-motor couplings that accompany purposeful motion. In this report, reasons for suspecting SMC as the basis for intelligent behavior will be reviewed. A robot control system for autonomous behavior that uses learned SMC will be proposed. Techniques for the extraction of salient parameters from sensory and motor data will be discussed. Experiments with Robonaut will be discussed and preliminary data presented.

  5. Protect Their Eyes: An Eye Safety Guide for the Classroom.

    ERIC Educational Resources Information Center

    Ohio Society to Prevent Blindness, Columbus.

    This guide provides information on eye safety and aids educators, administrators, and supervisors in the development and implementation of eye safety programs. The American National Standards Institute (AMSI) requirements for both street and safety glasses; essential eyewear for safety in hazardous areas; the National Society to Prevent…

  6. Neuroendocrine mechanisms underlying sensory integration of social signals.

    PubMed

    O'Connell, L A; Rigney, M M; Dykstra, D W; Hofmann, H A

    2013-07-01

    Individuals integrate information about their environment into adaptive behavioural responses, yet how different sensory modalities contribute to these decisions and where in the brain this integration occurs is not well understood. We presented male cichlid fish (Astatotilapia burtoni) with sensory information in three social contexts: intruder challenge, reproductive opportunity and a socially neutral situation. We then measured behavioural and hormonal responses along with induction of the immediate early gene c-Fos in candidate forebrain regions. In the intruder challenge context, males were exposed to either a visual stimulus of a dominant male, the putative male pheromone androstenedione, or both. We found that, compared to the neutral context, a visual stimulus was necessary and sufficient for an aggressive response, whereas both chemical and visual stimuli were needed for an androgen response. In the reproductive opportunity context, males were exposed to either a visual stimulus of a receptive female, a progesterone metabolite (female pheromone) only, or both. We further found that the visual stimulus is necessary and sufficient for an androgen response in the reproductive opportunity context. In the brain, we observed c-Fos induction in response to a visual challenge stimulus specifically in dopaminergic neurones of area Vc (the central region of the ventral telencephalon), a putative striatal homologue, whereas presentation of a chemical stimulus did not induce c-Fos induction in the intruder challenge context. Our results suggest that different sensory cues are processed in a social context-specific manner as part of adaptive decision-making processes. PMID:23631684

  7. P50 sensory gating and attentional performance.

    PubMed

    Wan, Li; Friedman, Bruce H; Boutros, Nash N; Crawford, Helen J

    2008-02-01

    Sensory gating refers to the preattentional filtering of irrelevant sensory stimuli. This process may be impaired in schizotypy, which is a trait also associated with cigarette smoking. This association may in part stem from the positive effects of smoking on sensory gating and attention. The relationship among sensory gating, smoking, schizotypy and attention was examined in 39 undergraduates. Sensory gating was indexed by the P50 suppression paradigm, and attention was measured by the Attention Network Test (ANT) and a Stroop task. Results showed sensory gating to be positively correlated with performances on ANT and Stroop reflected in better alerting, less conflict between stimuli, faster reaction time, and greater accuracy. Smokers showed a pattern of a greater number of significant correlations between sensory gating and attention in comparison to non-smokers, although the relationship between sensory gating and attention was not affected by schizotypy. The majority of significant correlations were found in the region surrounding Cz. These findings are discussed relative to the potential modifying influence of smoking and schizotypy on sensory gating and attention. PMID:18036692

  8. FINE STRUCTURE OF THE EYE OF A CHAETOGNATH.

    PubMed

    EAKIN, R M; WESTFALL, J A

    1964-04-01

    Electron microscopy reveals a star-like pigment cell at the center of the eye of the arrow-worm, Sagitta scrippsae. Between the arms of the pigment cell are clusters of photoreceptor cell processes, each process consisting of: (1) a tubular segment containing longitudinally arranged microtubules about 500 A in diameter and 20 micro in length; (2) a remarkable conical body, composed of cords and large granules, situated at the base of the tubular segment; and (3) a connecting piece which, like that of rods and cones, connects the process with the sensory cell proper and through which runs a fibrillar apparatus consisting of nine peripheral double tubules. Beneath the connecting piece lies a typical centriole with a striated rootlet. The receptor cell process is deeply recessed into the sensory cell which may possess a corona of microvilli at its inner surface. A nerve fiber arises from the outer end of the cell and passes into the optic nerve. Additional features are some supporting cells, an external layer of flattened epithelial cells, and an over-all investment of basement membrane and thick fibrous capsule. The fine structure and function of these elements of the eye are discussed in relation to earlier studies with the light microscope. The ciliary nature of the photoreceptor cell process in S. scrippsae points to a probable evolutionary relationship of chaetognaths to echinoderms and chordates. PMID:14154485

  9. Wavefront Derived Refraction and Full Eye Biometry in Pseudophakic Eyes

    PubMed Central

    Mao, Xinjie; Banta, James T.; Ke, Bilian; Jiang, Hong; He, Jichang; Liu, Che; Wang, Jianhua

    2016-01-01

    Purpose To assess wavefront derived refraction and full eye biometry including ciliary muscle dimension and full eye axial geometry in pseudophakic eyes using spectral domain OCT equipped with a Shack-Hartmann wavefront sensor. Methods Twenty-eight adult subjects (32 pseudophakic eyes) having recently undergone cataract surgery were enrolled in this study. A custom system combining two optical coherence tomography systems with a Shack-Hartmann wavefront sensor was constructed to image and monitor changes in whole eye biometry, the ciliary muscle and ocular aberration in the pseudophakic eye. A Badal optical channel and a visual target aligning with the wavefront sensor were incorporated into the system for measuring the wavefront-derived refraction. The imaging acquisition was performed twice. The coefficients of repeatability (CoR) and intraclass correlation coefficient (ICC) were calculated. Results Images were acquired and processed successfully in all patients. No significant difference was detected between repeated measurements of ciliary muscle dimension, full-eye biometry or defocus aberration. The CoR of full-eye biometry ranged from 0.36% to 3.04% and the ICC ranged from 0.981 to 0.999. The CoR for ciliary muscle dimensions ranged from 12.2% to 41.6% and the ICC ranged from 0.767 to 0.919. The defocus aberrations of the two measurements were 0.443 ± 0.534 D and 0.447 ± 0.586 D and the ICC was 0.951. Conclusions The combined system is capable of measuring full eye biometry and refraction with good repeatability. The system is suitable for future investigation of pseudoaccommodation in the pseudophakic eye. PMID:27010674

  10. Some Rat Sensory Neurons in Culture Express Characteristics of Differentiated Pain Sensory Cells

    NASA Astrophysics Data System (ADS)

    Baccaglini, Paola I.; Hogan, Patrick G.

    1983-01-01

    Sensory neurons were dissociated from trigeminal ganglia or from dorsal root ganglia of rats, grown in culture, and examined for expression of properties of pain sensory cells. Many sensory neurons in culture are excited by low concentrations of capsaicin, reportedly a selective stimulus for pain sensory neurons. Many are excited by bradykinin, sensitized by prostaglandin E2, or specifically stained by an antiserum against substance P. These experiments provide a basis for the study of pain mechanisms in cell culture.

  11. Formation of the hurricane eye

    NASA Astrophysics Data System (ADS)

    Vigh, Jonathan L.

    This dissertation consists of three distinct studies which investigate aspects of eye formation. The first study reviews eye phenomenon in a variety of vortices ranging from simple vortices to the menagerie of geophysical vortices, emphasizing similarities and differences to the eyes formed in hurricanes. The hurricane eye is found to be a paradoxical structure imposed by conservation of angular momentum and the boundaries of the vortex. A comprehensive definition for hurricane eye formation is proposed and various eye formation mechanisms are summarized. The next study presents a simple theoretical argument to isolate the conditions under which a tropical cyclone can rapidly develop a warm-core thermal structure and subsequently approach a steady state. The theoretical argument is based on the balanced vortex model and, in particular, on the associated transverse circulation equation and the geopotential tendency equation. The transverse circulation and the temperature tendency in a tropical vortex depend not only on the diabatic forcing, but also on the spatial distributions of the static stability, the baroclinity, and the inertial stability. The vortex response to diabatic heating depends critically on whether the heating occurs in the low inertial stability region outside the radius of maximum wind or in the high inertial stability region inside the radius of maximum wind. This result suggests that rapid intensification is favored for storms which have at least some of the eyewall convection inside the radius of maximum wind. The development of an eye partially removes diabatic heating from the high inertial stability region of the storm center, yet rapid intensification may continue if the eyewall heating continues to become more efficient. As the warm core matures and static stability increases over the inner core, conditions there become less favorable for deep upright convection and the storm tends to approach a steady state. The final study characterizes the kinematic and thermodynamic changes that occur before, during, and after the initial eye formations of a broad set of Atlantic tropical cyclones. To obtain the requisite structure and intensity parameters, a new data set has been synthesized from the Vortex Data Messages transmitted by routine aircraft reconnaissance from 1989--2008. Intensity ranges are determined for the times when the eye/eyewall structure first appears in aircraft radar and infrared satellite imagery. The mean intensity at which an eye is first observed in both aircraft or satellite imagery is found to be 58 kt, somewhat lower than reported in previous studies. Changes about the time of eye formation are examined for intensity, the radius of maximum winds, the minimum Rossby radius of deformation, eye temperature and dew point temperature depression. Storms are found to intensify most rapidly near the time of eye formation, especially when a persistent eye is observed in infrared satellite imagery. Many storms which are forming eyes are found to undergo a substantial and rapid contraction in the radius of maximum winds during the 24-h period before the eye is observed; once the eye is present, this contraction slows or ceases. Strong warming at lower levels (850 or 700 hPa) of the eye is not observed to correlate well with the time in which the eye is first observed. Finally, observations suggest that the dynamical heating efficiency of the resulting eyewall increases even as the physical scale of the efficient heating region decreases. This allows the storm to continue intensifying even though the total inner core diabatic heating may decrease. The answer to why some storms fail to form eyes may shed light on whether eye formation is a stochastic process involving constructive and destructive mesoscale interactions---or whether it is a manifold attractor of the system sometimes stymied by an unfavorable environment.

  12. Dominant Leadership Style in Schools

    ERIC Educational Resources Information Center

    Rajbhandari, Mani Man Singh

    2006-01-01

    The dominant leadership style is defined by the situation and the kind of organizational environment and climate. This, however, does not sufficiently define the leadership qualities in school organizations. There are other factors which also determine the dominant leadership style, which are the traits and style, teachers commitments, pass out…

  13. Novel TMEM98 mutations in pedigrees with autosomal dominant nanophthalmos

    PubMed Central

    Khorram, David; Choi, Michael; Roos, Ben R.; Stone, Edwin M.; Kopel, Teresa; Allen, Richard; Alward, Wallace L.M.; Scheetz, Todd E.

    2015-01-01

    Purpose Autosomal dominant nanophthalmos is an inherited eye disorder characterized by a structurally normal but smaller eye. Patients with nanophthalmos have high hyperopia (far-sightedness), a greater incidence of angle-closure glaucoma, and increased risk of surgical complications. In this study, the clinical features and the genetic basis of nanophthalmos were investigated in two large autosomal dominant nanophthalmos pedigrees. Methods Fourteen members of a Caucasian pedigree from the United States and 15 members of a pedigree from the Mariana Islands enrolled in a genetic study of nanophthalmos and contributed DNA samples. Twenty of 29 family members underwent eye examinations that included measurement of axial eye length and/or refractive error. The genetic basis of nanophthalmos in the pedigrees was studied with linkage analysis, whole exome sequencing, and candidate gene (i.e., TMEM98) sequencing to identify the nanophthalmos-causing gene. Results Nine members of the pedigree from the United States and 11 members of the pedigree from the Mariana Islands were diagnosed with nanophthalmos that is transmitted as an autosomal dominant trait. The patients with nanophthalmos had abnormally short axial eye lengths, which ranged from 15.9 to 18.4 mm. Linkage analysis of the nanophthalmos pedigree from the United States identified nine large regions of the genome (greater than 10 Mbp) that were coinherited with disease in this family. Genes within these “linked regions” were examined for disease-causing mutations using exome sequencing, and a His196Pro mutation was detected in the TMEM98 gene, which was recently reported to be a nanophthalmos gene. Sanger sequencing subsequently showed that all other members of this pedigree with nanophthalmos also carry the His196Pro TMEM98 mutation. Testing the Mariana Islands pedigree for TMEM98 mutations identified a 34 bp heterozygous deletion that spans the 3? end of exon 4 in all affected family members. Neither TMEM98 mutation was detected in public exome sequence databases. Conclusions A recent report identified a single TMEM98 missense mutation in a nanophthalmos pedigree. Our discovery of two additional TMEM98 mutations confirms the important role of the gene in the pathogenesis of autosomal dominant nanophthalmos. PMID:26392740

  14. Mechano- and Chemo-Sensory Polycystins

    NASA Astrophysics Data System (ADS)

    Patel, Amanda; Delmas, Patrick; Honoré, Eric

    Polycystins belong to the superfamily of transient receptor potential (TRP) channels and comprise five PKD1-like and three PKD2-like (TRPP) subunits. In this chapter, we review the general properties of polycystins and discuss their specific role in both mechanotransduction and chemoreception. The heteromer PKD1/PKD2 expressed at the membrane of the primary cilium of kidney epithelial cells is proposed to form a mechano-sensitive calcium channel that is opened by physiological fluid flow. Dysfunction or loss of PKD1 or PKD2 polycystin genes may be responsible for the inability of epithelial cells to sense mechanical cues, thus provoking autosomal dominant polycystic kidney disease (ADPKD), one of the most prevalent genetic kidney disorders. pkd1 and pkd2 knock-out mice recapitulate the human disease. Similarly, PKD2 may function as a mechanosensory calcium channel in the immotile monocilia of the developing node transducing leftward flow into an increase in calcium and specifying the left-right axis. pkd2, unlike pkd1 knock-out embryos are characterized by right lung isomerism (situs inversus). Mechanical stimuli also induce cleavage and nuclear translocation of the PKD1 C-terminal tail, which enters the nucleus and initiates signaling processes involving the AP-1, STAT6 and P100 pathways. This intraproteolytic mechanism is implicated in the transduction of a change in renal fluid flow to a transcriptional long-term response. The heteromer PKD1L3/PKD2L1 is the basis for acid sensing in specialised sensory cells including the taste bud cells responsible for sour taste. Moreover, PKD1L3/PKD2L1 may be implicated in the chemosensitivity of neurons surrounding the spinal cord canal, sensing protons in the cerebrospinal fluid. These recent results demonstrate that polycystins fulfill a major sensory role in a variety of cells including kidney epithelial cells, taste buds cells and spinal cord neurons. Such mechanisms are involved in short- and long-term physiological regulation. Alteration of these pathways culminates in severe human pathologies, including ADPKD.

  15. Sensory and motor properties of the cerebellar uvula and modulus

    NASA Technical Reports Server (NTRS)

    Robinson, F. R.

    1985-01-01

    The uvula and nodulus (vermal lobules 9 and 10) of the vestibulocerebellum are implicated by behavioral evidence in the control of eye and head movements and in the production of motion sickness. The uvula and nodulus could play a role in these functions through known output pathways. Purkinje cells in both structures project via the fastigial and vestibular nuceli to the ventral horn of the cervical spin cord, to oculomotor neurons, and to the emetic region of the reticular formation (ablation of which abolishes susceptability to motion sickness). Uvula and nodulus Purkinje cells will be analyzed in cats trained to make controlled head movements. The activity of these neurons is expected to modulate well during head and/or eye movements because the uvula and nodulus receive heavy projections from sources of visual, vestibular and neck proprioceptive information. How neuron activity contributes to movement and how different sensory inputs converge to influence this contribution may be determined by characterizing movement related properties of these neurons. A population of neurons that modulates powerfully to the conflict between different head movement signals that can cause motion sickness may be identified.

  16. Sensory Sensitivities and Performance on Sensory Perceptual Tasks in High-Functioning Individuals with Autism

    ERIC Educational Resources Information Center

    Minshew, Nancy J.; Hobson, Jessica A.

    2008-01-01

    Most reports of sensory symptoms in autism are second hand or observational, and there is little evidence of a neurological basis. Sixty individuals with high-functioning autism and 61 matched typical participants were administered a sensory questionnaire and neuropsychological tests of elementary and higher cortical sensory perception. Thirty-two…

  17. Sensory Sensitivities and Performance on Sensory Perceptual Tasks in High-Functioning Individuals with Autism

    ERIC Educational Resources Information Center

    Minshew, Nancy J.; Hobson, Jessica A.

    2008-01-01

    Most reports of sensory symptoms in autism are second hand or observational, and there is little evidence of a neurological basis. Sixty individuals with high-functioning autism and 61 matched typical participants were administered a sensory questionnaire and neuropsychological tests of elementary and higher cortical sensory perception. Thirty-two…

  18. Hemangiomas and the eye.

    PubMed

    Spence-Shishido, Allyson A; Good, William V; Baselga, Eulalia; Frieden, Ilona J

    2015-01-01

    Infantile hemangiomas are a common vascular birthmark with heterogeneous presentations and unique growth characteristics with early rapid growth and eventual self-involution. Hemangiomas that develop around the eye have the potential for inducing amblyopia by several mechanisms and may eventually result in permanent visual impairment in otherwise healthy infants. Segmental periocular hemangiomas carry the additional risk of associated structural anomalies and PHACE syndrome. In recent years, the treatment of periocular hemangiomas has been revolutionized by the serendipitous discovery of the effectiveness of beta-blockers (systemic and topical), with most experts viewing these as first-line therapies. The management of periocular hemangiomas should involve a close partnership between an ophthalmologist and dermatologist or other relevant specialists familiar with the unique clinical features, differential diagnosis, treatment approaches, and potential complications. PMID:25704937

  19. Microoptical telescope compound eye

    NASA Astrophysics Data System (ADS)

    Duparré, Jacques W.; Schreiber, Peter; Matthes, André; Pshenay–Severin, Ekaterina; Bräuer, Andreas; Tünnermann, Andreas; Völkel, Reinhard; Eisner, Martin; Scharf, Toralf

    2005-02-01

    A new optical concept for compact digital image acquisition devices with large field of view is developed and proofed experimentally. Archetypes for the imaging system are compound eyes of small insects and the Gabor Superlens. A paraxial 3x3 matrix formalism is used to describe the telescope arrangement of three microlens arrays with different pitch to find first order parameters of the imaging system. A 2mm thin imaging system with 21x3 channels, 70ºx10º field of view and 4.5mm x 0.5mm image size is optimized and analyzed using sequential and non sequential raytracing and fabricated by microoptics technology. Anamorphic lenses, where the parameters are a function of the considered optical channel, are used to achieve a homogeneous optical performance over the whole field of view. Captured images are presented and compared to simulation results.

  20. Eyes of Ganges

    NASA Technical Reports Server (NTRS)

    2005-01-01

    21 December 2005 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows eroded, light-toned layered rock outcrops on the side of a large mound in Ganges Chasma, part of the vast Valles Marineris trough system. Perhaps a testament to the inherent human (and primate) ability to pick out faces where partially hidden from view (even when a face is not really there) -- near the top of this picture are two features, each a product of erosion, resembling a pair of human eyes. This picture was acquired in late November 2005.

    Location near: 7.1oS, 49.4oW Image width: width: 0.55 km (0.3 mi) Illumination from: left/lower left Season: Southern Summer

  1. Dry eye disease after LASIK

    PubMed Central

    Ţuru, L; Alexandrescu, C; Stana, D; Tudosescu, R

    2012-01-01

    LASIK is a surgical tehnique for the correction of refractive errors (myopia, hyperopia, astygmatism). It results in a reshape of the cornea with ocular surface and especially tear film disease. It is a cause for a iatrogenic dry eye syndrome. Neurogenic and inflamatory theory explain this disease. The main therapy of dry eye is the replacement with artificial tears. PMID:22574092

  2. Eye Injuries Can Be Prevented.

    ERIC Educational Resources Information Center

    PTA Today, 1987

    1987-01-01

    Eleven thousand eye injuries are suffered annually by 5- to-14-year-old youngsters during sports and recreational activities. Baseball-related accidents result in more eye injuries to youth than any other sport. Protective face gear is discussed and recommended. (MT)

  3. Penetrating eye injury in war.

    PubMed

    Biehl, J W; Valdez, J; Hemady, R K; Steidl, S M; Bourke, D L

    1999-11-01

    The percentage of penetrating eye injuries in war has increased significantly in this century compared with the total number of combat injuries. With the increasing use of fragmentation weapons and possibly laser weapons on the battle-field in the future, the rate of eye injuries may exceed the 13% of the total military injuries found in Operations Desert Storm/Shield. During the Iran-Iraq War (1980-1988), eye injuries revealed that retained foreign bodies and posterior segment injuries have an improved prognosis in future military ophthalmic surgery as a result of modern diagnostic and treatment modalities. Compared with the increasing penetrating eye injuries on the battlefield, advances in ophthalmic surgery are insignificant. Eye armor, such as visors that flip up and down and protect the eyes from laser injury, needs to be developed. Similar eye protection is being developed in civilian sportswear. Penetrating eye injury in the civilian sector is becoming much closer to the military model and is now comparable for several reasons. PMID:10578588

  4. Miniature curved artificial compound eyes

    PubMed Central

    Floreano, Dario; Pericet-Camara, Ramon; Viollet, Stéphane; Ruffier, Franck; Brückner, Andreas; Leitel, Robert; Buss, Wolfgang; Menouni, Mohsine; Expert, Fabien; Juston, Raphaël; Dobrzynski, Michal Karol; L’Eplattenier, Geraud; Recktenwald, Fabian; Mallot, Hanspeter A.; Franceschini, Nicolas

    2013-01-01

    In most animal species, vision is mediated by compound eyes, which offer lower resolution than vertebrate single-lens eyes, but significantly larger fields of view with negligible distortion and spherical aberration, as well as high temporal resolution in a tiny package. Compound eyes are ideally suited for fast panoramic motion perception. Engineering a miniature artificial compound eye is challenging because it requires accurate alignment of photoreceptive and optical components on a curved surface. Here, we describe a unique design method for biomimetic compound eyes featuring a panoramic, undistorted field of view in a very thin package. The design consists of three planar layers of separately produced arrays, namely, a microlens array, a neuromorphic photodetector array, and a flexible printed circuit board that are stacked, cut, and curved to produce a mechanically flexible imager. Following this method, we have prototyped and characterized an artificial compound eye bearing a hemispherical field of view with embedded and programmable low-power signal processing, high temporal resolution, and local adaptation to illumination. The prototyped artificial compound eye possesses several characteristics similar to the eye of the fruit fly Drosophila and other arthropod species. This design method opens up additional vistas for a broad range of applications in which wide field motion detection is at a premium, such as collision-free navigation of terrestrial and aerospace vehicles, and for the experimental testing of insect vision theories. PMID:23690574

  5. Miniature curved artificial compound eyes.

    PubMed

    Floreano, Dario; Pericet-Camara, Ramon; Viollet, Stéphane; Ruffier, Franck; Brückner, Andreas; Leitel, Robert; Buss, Wolfgang; Menouni, Mohsine; Expert, Fabien; Juston, Raphaël; Dobrzynski, Michal Karol; L'Eplattenier, Geraud; Recktenwald, Fabian; Mallot, Hanspeter A; Franceschini, Nicolas

    2013-06-01

    In most animal species, vision is mediated by compound eyes, which offer lower resolution than vertebrate single-lens eyes, but significantly larger fields of view with negligible distortion and spherical aberration, as well as high temporal resolution in a tiny package. Compound eyes are ideally suited for fast panoramic motion perception. Engineering a miniature artificial compound eye is challenging because it requires accurate alignment of photoreceptive and optical components on a curved surface. Here, we describe a unique design method for biomimetic compound eyes featuring a panoramic, undistorted field of view in a very thin package. The design consists of three planar layers of separately produced arrays, namely, a microlens array, a neuromorphic photodetector array, and a flexible printed circuit board that are stacked, cut, and curved to produce a mechanically flexible imager. Following this method, we have prototyped and characterized an artificial compound eye bearing a hemispherical field of view with embedded and programmable low-power signal processing, high temporal resolution, and local adaptation to illumination. The prototyped artificial compound eye possesses several characteristics similar to the eye of the fruit fly Drosophila and other arthropod species. This design method opens up additional vistas for a broad range of applications in which wide field motion detection is at a premium, such as collision-free navigation of terrestrial and aerospace vehicles, and for the experimental testing of insect vision theories. PMID:23690574

  6. Photographic Screening for Eye Defects

    NASA Technical Reports Server (NTRS)

    Richardson, J.

    1985-01-01

    Images of retinas examined for characteristic patterns. Color photographs of retinas taken. Proper alinement of eye obtained by asking subject to gaze at light-emitting diode. "Red-eye" patterns in resulting color photographs examined by trained observers for signs of ocular defects. System used to check power of contact lenses and eyeglasses by taking photographs with these items in place.

  7. Purkinje cell responses during visually and vestibularly driven smooth eye movements in mice

    PubMed Central

    Katoh, Akira; Shin, Soon-Lim; Kimpo, Rhea R; Rinaldi, Jacob M; Raymond, Jennifer L

    2015-01-01

    Introduction An essential complement to molecular-genetic approaches for analyzing the function of the oculomotor circuitry in mice is an understanding of sensory and motor signal processing in the circuit. Although there has been extensive analysis of the signals carried by neurons in the oculomotor circuits of species, such as monkeys, rabbits and goldfish, relatively little in vivo physiology has been done in the oculomotor circuitry of mice. We analyzed the contribution of vestibular and nonvestibular signals to the responses of individual Purkinje cells in the cerebellar flocculus of mice. Methods We recorded Purkinje cells in the cerebellar flocculus of C57BL/6 mice during eye movement responses to vestibular and visual stimulation. Results As in other species, most individual Purkinje cells in mice carried both vestibular and nonvestibular signals, and the most common response across cells was an increase in firing in response to ipsiversive eye movement or ipsiversive head movement. When both the head and eyes were moving, the Purkinje cell responses were approximated as a linear summation of head and eye velocity inputs. Unlike other species, floccular Purkinje cells in mice were considerably more sensitive to eye velocity than head velocity. Conclusions The signal content of Purkinje cells in the cerebellar flocculus of mice was qualitatively similar to that in other species. However, the eye velocity sensitivity was higher than in other species, which may reflect a tuning to the smaller range of eye velocities in mice. PMID:25642393

  8. The Colossal Cosmic Eye

    NASA Astrophysics Data System (ADS)

    2005-09-01

    Eighty-five million years ago on small planet Earth, dinosaurs ruled, ignorant of their soon-to-come demise in the great Jurassic extinction, while mammals were still small and shy creatures. The southern Andes of Bolivia, Chile, and Argentina were not yet formed and South America was still an island continent. Eighty-five million years ago, our Sun and its solar system was 60,000 light years away from where it now stands [1]. Eighty-five million years ago, in another corner of the Universe, light left the beautiful spiral galaxy NGC 1350, for a journey across the universe. Part of this light was recorded at the beginning of the year 2000 AD by ESO's Very Large Telescope, located on the 2,600m high Cerro Paranal in the Chilean Andes on planet Earth. Astronomers classify NGC 1350 as an Sa(r) type galaxy, meaning it is a spiral with large central regions. In fact, NGC 1350 lies at the border between the broken-ring spiral type and a grand design spiral with two major outer arms. It is about 130,000 light-years across and, hence, is slightly larger than our Milky Way. The rather faint and graceful outer arms originate at the inner main ring and can be traced for almost half a circle when they each meet the opposite arm, giving the impression of completing a second outer ring, the "eye". The arms are given a blue tint as a result of the presence of very young and massive stars. The amount of dust, seen as small fragmented dust spirals in the central part of the galaxy and producing a fine tapestry that bear resemblance with blood vessels in the eye, is also a signature of the formation of stars.

  9. Abnormal cortical sensory activation in dystonia: an fMRI study.

    PubMed

    Butterworth, Stephen; Francis, Sue; Kelly, Edward; McGlone, Francis; Bowtell, Richard; Sawle, Guy V

    2003-06-01

    Despite the obvious motor manifestations of focal dystonia, it is recognised that the sensory system plays an important role in this condition. This functional magnetic resonance imaging study examines the sensory representations of individual digits both within the subregions of the primary sensory cortex (SI) and in other nonprimary sensory areas. Patients with focal dystonia and controls were scanned during vibrotactile stimulation of both the index (digit 2) and little (digit 5) fingers of their dominant hand (which was the affected hand in all the dystonic subjects). The activation maps obtained were analysed for location, size, and magnitude of activation and three-dimensional (3-D) orientation of digit representations. Data from both groups were compared. There were significant differences in the average 3-D separation between the two digit representations in area 1 of SI between subject groups (9.6 +/- 1.2 mm for controls and 4.1 +/- 0.2 mm for dystonic subjects). There were also strong trends for reversed ordering of the representation of the two digits in both the secondary sensory cortex and posterior parietal area between the two groups. In addition, in dystonic subjects, there was significant under activation in the secondary somatosensory cortex (SII/area 40) for both digits and in the posterior parietal area for digit 5. These results indicate the presence of widespread activation abnormalities in the cortical sensory system in dystonia. PMID:12784271

  10. Eye movements in Alzheimer's disease.

    PubMed

    Molitor, Robert J; Ko, Philip C; Ally, Brandon A

    2015-01-01

    A growing body of literature has investigated changes in eye movements as a result of Alzheimer's disease (AD). When compared to healthy, age-matched controls, patients display a number of remarkable alterations to oculomotor function and viewing behavior. In this article, we review AD-related changes to fundamental eye movements, such as saccades and smooth pursuit motion, in addition to changes to eye movement patterns during more complex tasks like visual search and scene exploration. We discuss the cognitive mechanisms that underlie these changes and consider the clinical significance of eye movement behavior, with a focus on eye movements in mild cognitive impairment. We conclude with directions for future research. PMID:25182738

  11. Ultrastructure and development of the rhabdomeric eyes in Lineus viridis (Heteronemertea, Nemertea).

    PubMed

    von Döhren, Jörn; Bartolomaeus, Thomas

    2007-01-01

    Nemerteans are undoubtedly members of the Spiralia, although their phylogenetic relationships are still a matter of debate. The apparently acoelomate organization suggests a relationship with the platyhelminths, whereas the blood-vascular system has been interpreted as an equivalent to coelomic cavities of annelids, indicating a close relation between annelids and nemerteans. Like other spiralians, most nemertean species are known to have one or several pairs of rhabdomeric and subepidermally situated eyes when adult. The development of these eyes as well as the mode in which the eyes are multiplied is as yet unknown. This is the first attempt to investigate eye formation in a nemertean. In the heteronemertean Lineus viridis (Müller, 1774) the everse rhabdomeric eyes are located deeply underneath the epidermis and consist of a few pigment cells that form a cup-like structure with interdigitating processes that contain numerous pigment granules. In hatchlings, the optical cavity contains processes of 12 sensory cells, each bearing a single cilium and various microvilli. The perikarya of these cells are located distally from the pigment cup. During further development the number of cells increases. Eye development starts with a small anlage situated underneath the epidermis, irrespective of whether this is the first eye or any additional one. The anlage consists of five unpigmented cells and three dendritic processes, each bearing apical microvilli and a single cilium. There is no evidence for an epidermal origin of the eyes. In L. viridis eye formation resembles that described in platyhelminths in which eyes also develop as cerebral derivatives. Although this result has the potential to influence the discussion on the position of Nemertea, the data have to be interpreted with care, since development of L. viridis is derived within the Nemertea. PMID:17913481

  12. Introduction to Symptoms of Eye Disorders

    MedlinePLUS

    ... Unequal Vision, Blurred Vision, Double Changes in the Appearance of the Eyes Vision Loss, Sudden Other Eye ... may involve changes in vision, changes in the appearance of the eye, or an abnormal sensation in ...

  13. Genetics Home Reference: Fish-eye disease

    MedlinePLUS

    ... Recent literature OMIM Genetic disorder catalog Conditions > Fish-eye disease On this page: Description Genetic changes Inheritance ... Glossary definitions Reviewed August 2013 What is fish-eye disease? Fish-eye disease, also called partial LCAT ...

  14. Testosterone and dominance in men.

    PubMed

    Mazur, A; Booth, A

    1998-06-01

    In men, high levels of endogenous testosterone (T) seem to encourage behavior intended to dominate--to enhance one's status over--other people. Sometimes dominant behavior is aggressive, its apparent intent being to inflict harm on another person, but often dominance is expressed nonaggressively. Sometimes dominant behavior takes the form of antisocial behavior, including rebellion against authority and low breaking. Measurement of T at a single point in time, presumably indicative of a man's basal T level, predicts many of these dominant or antisocial behaviors. T not only affects behavior but also responds to it. The act of competing for dominant status affects male T levels in two ways. First, T rises in the face of a challenge, as if it were an anticipatory response to impending competition. Second, after the competition, T rises in winners and declines in losers. Thus, there is a reciprocity between T and dominance behavior, each affecting the other. We contrast a reciprocal model, in which T level is variable, acting as both a cause and effect of behavior, with a basal model, in which T level is assumed to be a persistent trait that influences behavior. An unusual data set on Air Force veterans, in which data were collected four times over a decade, enables us to compare the basal and reciprocal models as explanations for the relationship between T and divorce. We discuss sociological implications of these models. PMID:10097017

  15. Measuring Sensory Reactivity in Autism Spectrum Disorder: Application and Simplification of a Clinician-Administered Sensory Observation Scale

    ERIC Educational Resources Information Center

    Tavassoli, Teresa; Bellesheim, Katherine; Siper, Paige M.; Wang, A. Ting; Halpern, Danielle; Gorenstein, Michelle; Grodberg, David; Kolevzon, Alexander; Buxbaum, Joseph D.

    2016-01-01

    Sensory reactivity is a new DSM-5 criterion for autism spectrum disorder (ASD). The current study aims to validate a clinician-administered sensory observation in ASD, the Sensory Processing Scale Assessment (SPS). The SPS and the Short Sensory Profile (SSP) parent-report were used to measure sensory reactivity in children with ASD (n = 35) and…

  16. Regulative capacity for eye formation by first quartet micromeres of the polychaete Capitella teleta.

    PubMed

    Yamaguchi, Emi; Dannenberg, Leah C; Amiel, Aldine R; Seaver, Elaine C

    2016-02-01

    The stereotypic cleavage pattern shared by spiralian embryos provides unique opportunities to compare mechanisms of cell fate specification of homologous blastomeres, and can give insights into how changes in fate may have influenced the evolution of novel structures and morphological diversity. The potential of cells to undergo regulation and the timing of cell fate specification were investigated during early development in the polychaete annelid, Capitella teleta. Targeted laser deletions of the first quartet micromeres were performed, with a focus on the eye-forming cells 1a and 1c. Most of the larvae resulting from deletion of the 1a or 1c micromeres lack both the pigment cell and sensory cell of the eye as predicted by the C. teleta fate map. In a minority of cases, however, both left and right larval eye spots develop, suggesting that other blastomeres within the embryo regulate for loss of these cells. Deletion of the 1a and 1c derivatives, 1a(1) or 1c(1), also largely result in larvae with one pigment spot, although there are larvae with two eye spots, suggesting that the ability to regulate for loss of an eye-generating cell persists for an additional cell cycle. Cell deletion in conjunction with intracellular labeling indicates that all four quadrants retain the ability to generate eyes, including those that normally do not. Deletion of all four first quartet micromeres provides evidence that only the first quartet micromeres have eye-forming potential. Additionally, in contrast to the right side of the head where larval and adult eye sensory cells are derived from the same cell (1c), on the left side, the larval and adult eye sensory cells are generated by different embryonic lineages. We hypothesize that cell-cell interactions and cell position are important for regulative ability in Capitella. To our knowledge, this is one of the first detailed deletion studies of the first quartet micromeres and the first convincing example of regulation in polychaetes, which are often thought to be non-regulative in nature. PMID:26702513

  17. Sensory innervation of white adipose tissue.

    PubMed

    Fishman, R B; Dark, J

    1987-12-01

    The presumption that sensory information does not arise from white adipose tissue was reevaluated using the neuroanatomical tracer, "true blue." Fluorescent cell bodies were observed in dorsal root ganglia of rats after tracer was implanted into inguinal or dorsal subcutaneous fat depots. Sensory information from adipose tissue may play an important role in the regulation of regional and total body fat mass. PMID:3425770

  18. Sensory characteristics of diverse rice cultivars

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Lack of a knowledge-base for predicting how genetic, pre-harvest, and post-harvest factors affect the sensory characteristics of rice results in producers and processors not having control over the sensory quality of their products. In this study, differences in the texture and flavor of seventeen ...

  19. Multiple Output Sensory Trainer (MOST). Final Report.

    ERIC Educational Resources Information Center

    Automated Functions, Inc., Arlington, VA.

    This final report describes the design, development, and testing of the Multiple Output Sensory Trainer (MOST), a computer-based system which enables the evaluation of students with visual impairments to determine the optimal combination of sensory adaptive aids to meet their needs. The system uses multimedia devices in conjunction with customized…

  20. Examination Accommodations for Students with Sensory Defensiveness

    ERIC Educational Resources Information Center

    Lewis, Kieran; Nolan, Clodagh

    2013-01-01

    Traditional examination accommodations include extra time, scribes, and/or separate venues for students with disabilities, which have been proven to be successful for the majority of students. For students with non-apparent disabilities such as sensory defensiveness, where sensitivity to a range of sensory information from the environment can…

  1. Nicotinic Acetylcholine Receptors in Sensory Cortex

    ERIC Educational Resources Information Center

    Metherate, Raju

    2004-01-01

    Acetylcholine release in sensory neocortex contributes to higher-order sensory function, in part by activating nicotinic acetylcholine receptors (nAChRs). Molecular studies have revealed a bewildering array of nAChR subtypes and cellular actions; however, there is some consensus emerging about the major nAChR subtypes and their functions in…

  2. ASIC3 Channels in Multimodal Sensory Perception

    PubMed Central

    2010-01-01

    Acid-sensing ion channels (ASICs), which are members of the sodium-selective cation channels belonging to the epithelial sodium channel/degenerin (ENaC/DEG) family, act as membrane-bound receptors for extracellular protons as well as nonproton ligands. At least five ASIC subunits have been identified in mammalian neurons, which form both homotrimeric and heterotrimeric channels. The highly proton sensitive ASIC3 channels are predominantly distributed in peripheral sensory neurons, correlating with their roles in multimodal sensory perception, including nociception, mechanosensation, and chemosensation. Different from other ASIC subunit composing ion channels, ASIC3 channels can mediate a sustained window current in response to mild extracellular acidosis (pH 7.3−6.7), which often occurs accompanied by many sensory stimuli. Furthermore, recent evidence indicates that the sustained component of ASIC3 currents can be enhanced by nonproton ligands including the endogenous metabolite agmatine. In this review, we first summarize the growing body of evidence for the involvement of ASIC3 channels in multimodal sensory perception and then discuss the potential mechanisms underlying ASIC3 activation and mediation of sensory perception, with a special emphasis on its role in nociception. We conclude that ASIC3 activation and modulation by diverse sensory stimuli represent a new avenue for understanding the role of ASIC3 channels in sensory perception. Furthermore, the emerging implications of ASIC3 channels in multiple sensory dysfunctions including nociception allow the development of new pharmacotherapy. PMID:22778854

  3. Phylostratigraphic profiles reveal a deep evolutionary history of the vertebrate head sensory systems

    PubMed Central

    2013-01-01

    Background The vertebrate head is a highly derived trait with a heavy concentration of sophisticated sensory organs that allow complex behaviour in this lineage. The head sensory structures arise during vertebrate development from cranial placodes and the neural crest. It is generally thought that derivatives of these ectodermal embryonic tissues played a central role in the evolutionary transition at the onset of vertebrates. Despite the obvious importance of head sensory organs for vertebrate biology, their evolutionary history is still uncertain. Results To give a fresh perspective on the adaptive history of the vertebrate head sensory organs, we applied genomic phylostratigraphy to large-scale in situ expression data of the developing zebrafish Danio rerio. Contrary to traditional predictions, we found that dominant adaptive signals in the analyzed sensory structures largely precede the evolutionary advent of vertebrates. The leading adaptive signals at the bilaterian-chordate transition suggested that the visual system was the first sensory structure to evolve. The olfactory, vestibuloauditory, and lateral line sensory organs displayed a strong link with the urochordate-vertebrate ancestor. The only structures that qualified as genuine vertebrate innovations were the neural crest derivatives, trigeminal ganglion and adenohypophysis. We also found evidence that the cranial placodes evolved before the neural crest despite their proposed embryological relatedness. Conclusions Taken together, our findings reveal pre-vertebrate roots and a stepwise adaptive history of the vertebrate sensory systems. This study also underscores that large genomic and expression datasets are rich sources of macroevolutionary information that can be recovered by phylostratigraphic mining. PMID:23587066

  4. Thermoelectricity and noncellular sensory transduction

    NASA Astrophysics Data System (ADS)

    Brown, Brandon

    2003-03-01

    Sharks and rays possess electrosensors that provide environmental data assisting such tasks as prey detection and mate location. These organs are also incredibly sensitive to minute changes in temperature, and their reaction to temperature is unlike any other thermoreceptor known in nature. We have collected samples of the extracellular gel that fills the electrosensitive organs, and, while characterizing its material properties, we have found an average thermopower of roughly 300 microvolts/Kelvin. We will discuss the implications of these data in terms of a novel, noncellular mode of sensory transduction, in which a thermal fluctuation is translated into an electrical stimulus by the gel. We will also contrast the gel to more established thermoelectric materials.

  5. Sensory signals during active versus passive movement.

    PubMed

    Cullen, Kathleen E

    2004-12-01

    Our sensory systems are simultaneously activated as the result of our own actions and changes in the external world. The ability to distinguish self-generated sensory events from those that arise externally is thus essential for perceptual stability and accurate motor control. Recently, progress has been made towards understanding how this distinction is made. It has been proposed that an internal prediction of the consequences of our actions is compared to the actual sensory input to cancel the resultant self-generated activation. Evidence in support of this hypothesis has been obtained for early stages of sensory processing in the vestibular, visual and somatosensory systems. These findings have implications for the sensory-motor transformations that are needed to guide behavior. PMID:15582371

  6. Body-scaled affordances in sensory substitution.

    PubMed

    Travieso, David; Gómez-Jordana, Luis; Díaz, Alex; Lobo, Lorena; Jacobs, David M

    2015-12-15

    The research field on sensory substitution devices has strong implications for theoretical work on perceptual consciousness. One of these implications concerns the extent to which the devices allow distal attribution. The present study applies a classic empirical approach on the perception of affordances to the field of sensory substitution. The reported experiment considers the perception of the stair-climbing affordance. Participants judged the climbability of steps apprehended through a vibrotactile sensory substitution device. If measured with standard metric units, climbability judgments of tall and short participants differed, but if measured in units of leg length, judgments did not differ. These results are similar to paradigmatic results in regular visual perception. We conclude that our sensory substitution device allows the perception of affordances. More generally, we argue that the theory of affordances may enrich theoretical debates concerning sensory substitution to a larger extent than has hitherto been the case. PMID:26587958

  7. Sensory sensitivities and performance on sensory perceptual tasks in high-functioning individuals with autism

    PubMed Central

    Minshew, Nancy J.; Hobson, Jessica A.

    2011-01-01

    Despite extensive reports of sensory symptoms in autism, there is little empirical support for their neurological basis. Sixty individuals with high-functioning autism and 61 matched typical comparison participants were administered a sensory questionnaire and standardized neuropsychological tests of elementary and higher cortical sensory perception. Thirty-two per cent of participants with autism endorsed more sensory sensitivity items than any of the participants in the comparison group. On the sensory perceptual exam, both groups made few errors on elementary sensory perception items. Controls made few errors on higher cortical sensory perception items, but 30% of the participants with autism made high numbers of errors, though there was no evidence of the neglect syndrome. There was little correlation between the sensory sensitivities and the sensory perceptual deficits, likely due to the low correspondence between the measures. These results support the common occurrence of disturbances in sensory experiences in high functioning individuals with autism based on first person report, and the presence of neurological abnormalities in higher cortical sensory perception. PMID:18302014

  8. Genetics Home Reference: Hereditary sensory and autonomic neuropathy type IE

    MedlinePLUS

    ... Genetic disorder catalog Conditions > Hereditary sensory and autonomic neuropathy type IE On this page: Description Genetic changes ... November 2012 What is hereditary sensory and autonomic neuropathy type IE? Hereditary sensory and autonomic neuropathy type ...

  9. Genetics Home Reference: Hereditary sensory neuropathy type IA

    MedlinePLUS

    ... literature OMIM Genetic disorder catalog Conditions > Hereditary sensory neuropathy type IA On this page: Description Genetic changes ... definitions Reviewed March 2015 What is hereditary sensory neuropathy type IA? Hereditary sensory neuropathy type IA is ...

  10. Lateral Dominance and Reading Disability.

    ERIC Educational Resources Information Center

    Harris, Albert J.

    1979-01-01

    Theory and research on the relation of lateral dominance to the causation of reading disability are reviewed. Both direct and indirect measures of cerebral hemisphere functioning are considered. (SBH)

  11. How to examine an eye.

    PubMed

    Marsden, Janet

    2015-11-25

    Rationale and key points This article aims to assist nurses to perform a systematic external examination of the eye with the minimum of equipment. The eyes form a complex anatomical system, about which nurses often lack confidence. ? Eye problems are a relatively common reason for presentation to emergency departments and primary care. ? The nurse requires a knowledge of the underlying anatomy and physiology to perform an eye examination. ? Nurses in non-specialist settings should be able to assess the integrity of the eye and decide whether specialist referral and examination is required. ? Eye examination requires few elements of equipment and should be systematic. Reflective activity Clinical skills articles can help update your practice and ensure it remains evidence based. Apply this article to your practice. Reflect on and write a short account of: 1. What further knowledge and skills you require to enable you to explain to the patient what might be occurring when they have an eye problem. 2. How you will gain this knowledge. Subscribers can upload their reflective accounts at: rcni.com/portfolio . PMID:26602677

  12. Superglue injuries of the eye

    PubMed Central

    Reddy, Sagili Chandrasekhara

    2012-01-01

    AIM To report various ocular lesions caused by accidental instillation of superglue. METHODS Three cases of ocular injuries are described in children aged 6 years, 3 years and 8 months, following accidental instillation of superglue in the eye. RESULTS In the first case there was sticking of eyelashes in the medial 1/3 of eyelids in both eyes. In the second case sticking of eye lashes was present in the lateral 1/3 of eyelids in the left eye. In the third case, superglue was present on the right cheek, above the right ear and sticking of eyelids in medial 1/3 in right eye. The eyelids were separated by pulling the lid margins with fingers in the first case and later on superglue was removed by trimming the eyelashes; and by direct trimming the eyelashes in second and third cases. There was no injury to other structures of anterior segment in the first two cases. However, removal of the superglue on the cornea resulted in corneal abrasion in the third case which healed with medical treatment and patching of the right eye. CONCLUSION Accidental instillation of superglue is possible because of the appearance of the tube like eye ointment tube. Immediate medical aid will prevent ocular morbidity. PMID:23166877

  13. Neural mechanisms of social dominance

    PubMed Central

    Watanabe, Noriya; Yamamoto, Miyuki

    2015-01-01

    In a group setting, individuals' perceptions of their own level of dominance or of the dominance level of others, and the ability to adequately control their behavior based on these perceptions are crucial for living within a social environment. Recent advances in neural imaging and molecular technology have enabled researchers to investigate the neural substrates that support the perception of social dominance and the formation of a social hierarchy in humans. At the systems' level, recent studies showed that dominance perception is represented in broad brain regions which include the amygdala, hippocampus, striatum, and various cortical networks such as the prefrontal, and parietal cortices. Additionally, neurotransmitter systems such as the dopaminergic and serotonergic systems, modulate and are modulated by the formation of the social hierarchy in a group. While these monoamine systems have a wide distribution and multiple functions, it was recently found that the Neuropeptide B/W contributes to the perception of dominance and is present in neurons that have a limited projection primarily to the amygdala. The present review discusses the specific roles of these neural regions and neurotransmitter systems in the perception of dominance and in hierarchy formation. PMID:26136644

  14. Insecticide resistance and dominance levels.

    PubMed

    Bourguet, D; Genissel, A; Raymond, M

    2000-12-01

    Dominance has been assessed in different ways in insecticide resistance studies, based on three phenotypic traits: the insecticide concentration required to give a particular mortality (DLC), mortality at a particular insecticide dose (DML), and fitness in treated areas (DWT). We propose a general formula for estimating dominance on a scale of 0 to 1 (0 = complete recessivity and 1 = complete dominance). DLC, DML, and DWT are not directly related and their values depend on genetic background and environmental conditions. We also show that pest management strategies can have the consequence to increase DWT via the selection of dominance modifiers. Studies on resistance to Bacillus thuringiensis toxins provide the ultimate example of the complexity of the definition of the concept of dominance. Almost all studies have focused on calculation of DLC, which provides little information about the efficiency of pest management programs. For instance, one assumption of the high dose/refuge strategy is that Bacillus thuringiensis resistance must be effectively recessive (i.e., DML must be close to zero). However, DWT, rather than DML, is relevant to the resistance management strategy. Therefore, we strongly suggest that the time has come to focus on fitness dominance levels in the presence and absence of insecticide. PMID:11142285

  15. A Small Motor Cortex Lesion Abolished Ocular Dominance Plasticity in the Adult Mouse Primary Visual Cortex and Impaired Experience-Dependent Visual Improvements

    PubMed Central

    Pielecka-Fortuna, Justyna; Kalogeraki, Evgenia; Greifzu, Franziska; Löwel, Siegrid

    2015-01-01

    It was previously shown that a small lesion in the primary somatosensory cortex (S1) prevented both cortical plasticity and sensory learning in the adult mouse visual system: While 3-month-old control mice continued to show ocular dominance (OD) plasticity in their primary visual cortex (V1) after monocular deprivation (MD), age-matched mice with a small photothrombotically induced (PT) stroke lesion in S1, positioned at least 1 mm anterior to the anterior border of V1, no longer expressed OD-plasticity. In addition, in the S1-lesioned mice, neither the experience-dependent increase of the spatial frequency threshold (“visual acuity”) nor of the contrast threshold (“contrast sensitivity”) of the optomotor reflex through the open eye was present. To assess whether these plasticity impairments can also occur if a lesion is placed more distant from V1, we tested the effect of a PT-lesion in the secondary motor cortex (M2). We observed that mice with a small M2-lesion restricted to the superficial cortical layers no longer expressed an OD-shift towards the open eye after 7 days of MD in V1 of the lesioned hemisphere. Consistent with previous findings about the consequences of an S1-lesion, OD-plasticity in V1 of the nonlesioned hemisphere of the M2-lesioned mice was still present. In addition, the experience-dependent improvements of both visual acuity and contrast sensitivity of the open eye were severely reduced. In contrast, sham-lesioned mice displayed both an OD-shift and improvements of visual capabilities of their open eye. To summarize, our data indicate that even a very small lesion restricted to the superficial cortical layers and more than 3mm anterior to the anterior border of V1 compromised V1-plasticity and impaired learning-induced visual improvements in adult mice. Thus both plasticity phenomena cannot only depend on modality-specific and local nerve cell networks but are clearly influenced by long-range interactions even from distant brain regions. PMID:26368569

  16. [Eye Myiasis - a Case Report].

    PubMed

    Kopecký, A; N?m?anský, J; Doležil, Z; Mašková, R; Mašek, P

    2015-09-01

    The authors describe a case of 47 years old patient who came to the department of ophthalmology with eye discomfort, ear bleeding and itching of both legs. The diagnosis of ophthalmomyiasis was made after an eye examination. Manual extraction of maggots from upper and lower fornix of the left eye was performed and symptomatic therapy was given. The patient was sent to otolaryngology and dermatology departments and MRI. The maggots were also found in both external auditory meatus and between the toes. MRI excluded affection of the deeper structures of the head. Improvement of the local condition was observed since the first follow-up visit. PMID:26782730

  17. An eye for an eye. A simplified model for teaching.

    PubMed

    Dodaro, N R; Maxwell, D P

    1995-06-01

    We developed an easily constructed, inexpensive eye model that consists of a Styrofoam head carved out to house a slide holder, a wide-angle, clinical photographic fundus slide, a plastic face, and an anatomically correct eye. The model can be used by students and residents to learn direct and indirect ophthalmoscopy, fundus photography, and laser photocoagulation. This model gives students and residents a realistic learning experience without inconveniencing or endangering patients. PMID:7786227

  18. Tunable compound eye cameras

    NASA Astrophysics Data System (ADS)

    Pätz, Daniel; Leopold, Steffen; Knöbber, Fabian; Sinzinger, Stefan; Hoffmann, Martin; Ambacher, Oliver

    2010-05-01

    We present design and realization concepts for thin compound eye cameras with enhanced optical functionality. The systems are based on facets with individually tunable focus lengths and viewing angles for scanning of the object space. The active lens elements are made of aluminum nitride (AlN)/nanocrystalline diamond (NCD) membranes. This material system allows slow thermally actuated elements with a large deformation range as well as fast piezoelectric elements with a smaller deformation range. Due to the extreme mechanical stability of these materials, we are able to realize microoptical components with optimum surface qualities as well as an excellent long-term stability. We use facets of microlenses with 1 mm in diameter and a tunable focusing power to compensate for the focus shift for different viewing angles during the scanning procedure. The beam deflection for scanning is realized either by laterally shifting spherical elements or by a tunable microprism with reduced aberrations. For both actuators we present a design, fabrication concept and first experimental results.

  19. Eyes in the Sky

    NASA Technical Reports Server (NTRS)

    2006-01-01

    These shape-shifting galaxies have taken on the form of a giant mask. The icy blue eyes are actually the cores of two merging galaxies, called NGC 2207 and IC 2163, and the mask is their spiral arms. The false-colored image consists of infrared data from NASA's Spitzer Space Telescope (red) and visible data from NASA's Hubble Space Telescope (blue/green).

    NGC 2207 and IC 2163 met and began a sort of gravitational tango about 40 million years ago. The two galaxies are tugging at each other, stimulating new stars to form. Eventually, this cosmic ball will come to an end, when the galaxies meld into one. The dancing duo is located 140 million light-years away in the Canis Major constellation.

    The infrared data from Spitzer highlight the galaxies' dusty regions, while the visible data from Hubble indicates starlight. In the Hubble-only image (not pictured here), the dusty regions appear as dark lanes.

    The Hubble data correspond to light with wavelengths of .44 and .55 microns (blue and green, respectively). The Spitzer data represent light of 8 microns.

  20. The ‘division of labour’ model of eye evolution

    PubMed Central

    Arendt, Detlev; Hausen, Harald; Purschke, Günter

    2009-01-01

    The ‘division of labour’ model of eye evolution is elaborated here. We propose that the evolution of complex, multicellular animal eyes started from a single, multi-functional cell type that existed in metazoan ancestors. This ancient cell type had at least three functions: light detection via a photoreceptive organelle, light shading by means of pigment granules and steering through locomotor cilia. Located around the circumference of swimming ciliated zooplankton larvae, these ancient cells were able to mediate phototaxis in the absence of a nervous system. This precursor then diversified, by cell-type functional segregation, into sister cell types that specialized in different subfunctions, evolving into separate photoreceptor cells, shading pigment cells (SPCs) or ciliated locomotor cells. Photoreceptor sensory cells and ciliated locomotor cells remained interconnected by newly evolving axons, giving rise to an early axonal circuit. In some evolutionary lines, residual functions prevailed in the specialized cell types that mirror the ancient multi-functionality, for instance, SPCs expressing an opsin as well as possessing rhabdomer-like microvilli, vestigial cilia and an axon. Functional segregation of cell types in eye evolution also explains the emergence of more elaborate photosensory–motor axonal circuits, with interneurons relaying the visual information. PMID:19720646

  1. Emerging functions of pannexin 1 in the eye

    PubMed Central

    Kurtenbach, Sarah; Kurtenbach, Stefan; Zoidl, Georg

    2014-01-01

    Pannexin 1 (Panx1) is a high-conductance, voltage-gated channel protein found in vertebrates. Panx1 is widely expressed in many organs and tissues, including sensory systems. In the eye, Panx1 is expressed in major divisions including the retina, lens and cornea. Panx1 is found in different neuronal and non-neuronal cell types. The channel is mechanosensitive and responds to changes in extracellular ATP, intracellular calcium, pH, or ROS/nitric oxide. Since Panx1 channels operate at the crossroad of major signaling pathways, physiological functions in important autocrine and paracrine feedback signaling mechanisms were hypothesized. This review starts with describing in depth the initial Panx1 expression and localization studies fostering functional studies that uncovered distinct roles in processing visual information in subsets of neurons in the rodent and fish retina. Panx1 is expressed along the entire anatomical axis from optical nerve to retina and cornea in glia, epithelial and endothelial cells as well as in neurons. The expression and diverse localizations throughout the eye points towards versatile functions of Panx1 in neuronal and non-neuronal cells, implicating Panx1 in the crosstalk between immune and neural cells, pressure related pathological conditions like glaucoma, wound repair or neuronal cell death caused by ischemia. Summarizing the literature on Panx1 in the eye highlights the diversity of emerging Panx1 channel functions in health and disease. PMID:25309318

  2. Summary of Eye Examinations of 284 Patients with Multiple Sclerosis

    PubMed Central

    2012-01-01

    The aim of this article is to report the findings of ocular examinations in a group of patients diagnosed with multiple sclerosis who were referred to the eye department of the Nationaal Multiple Sclerosis Centrum of Melsbroek, Belgium, from 2007 to 2010. Patients were evaluated by a single examiner, who noted visual acuity for distance, the state of the optic disks, oculomotor balance, and the presence of nystagmus, uveitis, trigeminal neuralgia, and facial palsy. The sample consisted of 284 adults born between 1920 and 1989: 111 males and 173 females. There were 51 patients with a corrected visual acuity in the better-seeing eye of less than 6/20. The optic nerve head was found to be normal in 245 eyes. Nystagmus was noted in 104 patients. Diplopia at distance was found to be present in 20 males, of whom 12 also had nystagmus, and in 31 females, of whom 13 also had nystagmus. Oscillopsia was present in 6 males and 11 females. In summary, most of the patients evaluated had sufficient visual function to allow performance of activities of daily living without help. A small number of patients had visual failure due to dysfunction of the visual sensory pathway and/or disturbances of oculomotor balance, often of a supranuclear origin, resulting in considerable disability. PMID:24453730

  3. Three dimensional eye movements of squirrel monkeys following postrotatory tilt

    NASA Technical Reports Server (NTRS)

    Merfeld, D. M.; Young, L. R.; Paige, G. D.; Tomko, D. L.

    1993-01-01

    Three-dimensional squirrel monkey eye movements were recorded during and immediately following rotation around an earth-vertical yaw axis (160 degrees/s steady state, 100 degrees/s2 acceleration and deceleration). To study interactions between the horizontal angular vestibulo-ocular reflex (VOR) and head orientation, postrotatory VOR alignment was changed relative to gravity by tilting the head out of the horizontal plane (pitch or roll tilt between 15 degrees and 90 degrees) immediately after cessation of motion. Results showed that in addition to post rotatory horizontal nystagmus, vertical nystagmus followed tilts to the left or right (roll), and torsional nystagmus followed forward or backward (pitch) tilts. When the time course and spatial orientation of eye velocity were considered in three dimensions, the axis of eye rotation always shifted toward alignment with gravity, and the postrotatory horizontal VOR decay was accelerated by the tilts. These phenomena may reflect a neural process that resolves the sensory conflict induced by this postrotatory tilt paradigm.

  4. Monitoring the eye lens: which dose quantity is adequate?

    NASA Astrophysics Data System (ADS)

    Behrens, R.; Dietze, G.

    2010-07-01

    Recent epidemiological studies suggest a rather low dose threshold (below 0.5 Gy) for the induction of a cataract of the eye lens. Some other studies even assume that there is no threshold at all. Therefore, protection measures have to be optimized and current dose limits for the eye lens may be reduced in the future. The question of which personal dose equivalent quantity is appropriate for monitoring the dose to the eye lens arises from this situation. While in many countries dosemeters calibrated in terms of the dose equivalent quantity Hp(0.07) have been seen as being adequate for monitoring the dose to the eye lens, this might be questionable in the case of reduced dose limits and, thus, it may become necessary to use the dose equivalent quantity Hp(3) for this purpose. To discuss this question, the dose conversion coefficients for the equivalent dose of the eye lens (in the following eye lens dose) were determined for realistic photon and beta radiation fields and compared with the values of the corresponding conversion coefficients for the different operational quantities. The values obtained lead to the following conclusions: in radiation fields where most of the dose comes from photons, especially x-rays, it is appropriate to use dosemeters calibrated in terms of Hp(0.07) on a slab phantom, while in other radiation fields (dominated by beta radiation or unknown contributions of photon and beta radiation) dosemeters calibrated in terms of Hp(3) on a slab phantom should be used. As an alternative, dosemeters calibrated in terms of Hp(0.07) on a slab phantom could also be used; however, in radiation fields containing beta radiation with the end point energy near 1 MeV, an overestimation of the eye lens dose by up to a factor of 550 is possible.

  5. "Visual sensory trick" in patient with cervical dystonia.

    PubMed

    Lee, Chan-Nyoung; Eun, Mi-Yeon; Kwon, Do-Young; Park, Moon Ho; Park, Kun-Woo

    2012-06-01

    Sensory tricks are clinical maneuvers that may partially relieve dystonic contractions. Any clinical maneuver that modulates afferent sensory and efferent motor pathways could be used as a sensory trick in patients with cervical dystonia. Although various sensory tricks have been described to reduce cervical dystonia, little is known about the exact mechanisms by which they operate. We report a case of cervical dystonia that was alleviated through the use of a visual-sensory trick. Our findings suggest that visual stimulation might be an effective sensory trick in cervical dystonia by compensating for a defective sensory system, or because visual pathways might be also affected by sensory interactions in cervical dystonia. PMID:22071793

  6. Sensory rehabilitation in the plastic brain.

    PubMed

    Collignon, Olivier; Champoux, François; Voss, Patrice; Lepore, Franco

    2011-01-01

    The purpose of this review is to consider new sensory rehabilitation avenues in the context of the brain's remarkable ability to reorganize itself following sensory deprivation. Here, deafness and blindness are taken as two illustrative models. Mainly, two promising rehabilitative strategies based on opposing theoretical principles will be considered: sensory substitution and neuroprostheses. Sensory substitution makes use of the remaining intact senses to provide blind or deaf individuals with coded information of the lost sensory system. This technique thus benefits from added neural resources in the processing of the remaining senses resulting from crossmodal plasticity, which is thought to be coupled with behavioral enhancements in the intact senses. On the other hand, neuroprostheses represent an invasive approach aimed at stimulating the deprived sensory system directly in order to restore, at least partially, its functioning. This technique therefore relies on the neuronal integrity of the brain areas normally dedicated to the deprived sense and is rather hindered by the compensatory reorganization observed in the deprived cortex. Here, we stress that our understanding of the neuroplastic changes that occur in sensory-deprived individuals may help guide the design and the implementation of such rehabilitative methods. PMID:21741554

  7. Sensory substitution as an artificially acquired synaesthesia.

    PubMed

    Ward, Jamie; Wright, Thomas

    2014-04-01

    In this review we explore the relationship between synaesthesia and sensory substitution and argue that sensory substitution does indeed show properties of synaesthesia. Both are associated with atypical perceptual experiences elicited by the processing of a qualitatively different stimulus to that which normally gives rise to that experience. In the most common forms of sensory substitution, perceptual processing of an auditory or tactile signal (which has been converted from a visual signal) is experienced as visual-like in addition to retaining auditory/tactile characteristics. We consider different lines of evidence that support, to varying degrees, the assumption that sensory substitution is associated with visual-like experiences. We then go on to analyse the key similarities and differences between sensory substitution and synaesthesia. Lastly, we propose two testable predictions: firstly that, in an expert user of a sensory substitution device, the substituting modality should not be lost. Secondly that stimulation within the substituting modality, but by means other than a sensory substitution device, should still produce sensation in the normally substituted modality. PMID:22885223

  8. Beyond words: Sensory properties of depressive thoughts

    PubMed Central

    Hörmann, Claudia Cecile; Schröder, Johanna; Berger, Thomas; Jacob, Gitta A.; Meyer, Björn; Holmes, Emily A.; Späth, Christina; Hautzinger, Martin; Lutz, Wolfgang; Rose, Matthias; Klein, Jan Philipp

    2013-01-01

    Verbal thoughts (such as negative cognitions) and sensory phenomena (such as visual mental imagery) are usually conceptualised as distinct mental experiences. The present study examined to what extent depressive thoughts are accompanied by sensory experiences and how this is associated with symptom severity, insight of illness and quality of life. A large sample of mildly to moderately depressed patients (N = 356) was recruited from multiple sources and asked about sensory properties of their depressive thoughts in an online study. Diagnostic status and symptom severity were established over a telephone interview with trained raters. Sensory properties of negative thoughts were reported by 56.5% of the sample (i.e., sensation in at least one sensory modality). The highest prevalence was seen for bodily (39.6%) followed by auditory (30.6%) and visual (27.2%) sensations. Patients reporting sensory properties of thoughts showed more severe psychopathological symptoms than those who did not. The degree of perceptuality was marginally associated with quality of life. The findings support the notion that depressive thoughts are not only verbal but commonly accompanied by sensory experiences. The perceptuality of depressive thoughts and the resulting sense of authenticity may contribute to the emotional impact and pervasiveness of such thoughts, making them difficult to dismiss for their holder. PMID:24359124

  9. Conjunctivitis (Pink Eye) in Newborns

    MedlinePLUS

    ... Antibiotics Work Adenovirus Non-Polio Enterovirus Parent Portal Conjunctivitis (Pink Eye) in Newborns Language: English Español (Spanish) ... conjunctivitis can be very serious. Types of Neonatal Conjunctivitis The most common types of neonatal conjunctivitis are ...

  10. Eye Movements and Conservation Acceleration

    ERIC Educational Resources Information Center

    Boersma, Frederic J.; Wilton, Keri M.

    1974-01-01

    Non conserving first- and second-grade children were tested on conservation tasks. Eye movements were recorded during the response period for each task. Trained conservers showed more visual exploratory behavior and less perceptual centration than control subjects. (ST)

  11. Eye movements when viewing advertisements.

    PubMed

    Higgins, Emily; Leinenger, Mallorie; Rayner, Keith

    2014-01-01

    In this selective review, we examine key findings on eye movements when viewing advertisements. We begin with a brief, general introduction to the properties and neural underpinnings of saccadic eye movements. Next, we provide an overview of eye movement behavior during reading, scene perception, and visual search, since each of these activities is, at various times, involved in viewing ads. We then review the literature on eye movements when viewing print ads and warning labels (of the kind that appear on alcohol and tobacco ads), before turning to a consideration of advertisements in dynamic media (television and the Internet). Finally, we propose topics and methodological approaches that may prove to be useful in future research. PMID:24672500

  12. RapidEye Library (Archive)

    NASA Astrophysics Data System (ADS)

    Jung-Rothenhausler, Frederik

    2010-12-01

    The RapidEye satellite system - a constellation of five satellites capable of downloading over 4 million km2 of high resolution, multi-spectral imagery per day, and a ground segment for processing and archiving data - allow for cost-effective customized services. The unique combination of large area coverage, high spatial resolution and the possibility of daily revisit to an area provide for superior management information solutions. Since RapidEye declared the system commercially operational in early 2009, RapidEye has collected an exceptional volume of global imagery data. 5m pixel spacing and large-area coverage capabilities make RapidEye data ideally suited for a broad spectrum of applications.

  13. Schematic eyes for domestic animals.

    PubMed

    Coile, D C; O'Keefe, L P

    1988-01-01

    Schematic and reduced eyes for the horse, cow, sheep, pig, cat, and dog were calculated from optical parameter values obtained from the literature. Calculations were performed with the aid of a computer program using standard Gaussian equations and a homogeneous lens model. Calculated schematic eyes had refractive states within 1.5 D of emmetropia; retinal image sizes ranged from 0.22 (cat and dog) to 0.44 (horse) mm/deg. The cat eye presented here is more nearly emmetropic than a previously published cat schematic eye. The effects of altering refractive indices, radii of curvature, and thicknesses of refractive components upon refractive state and retinal image size are examined. The largest differences resulted from changes made to refractive indices of the lens and vitreous and to the vitreous depth. PMID:3211562

  14. Applications of lobster eye optics

    NASA Astrophysics Data System (ADS)

    Hudec, R.; Pina, L.; Inneman, A.; Tichy, V.

    2015-05-01

    Applications of wide field Lobster Eye X ray telescopes are presented and discussed. The wide field X ray optics was originally proposed for use in X-ray astronomy, but there are numerous other application areas as well.

  15. Eye injuries in Canadian hockey.

    PubMed Central

    Pashby, T. J.; Pashby, R. C.; Chisholm, L. D.; Crawford, J. S.

    1975-01-01

    Increasing public concern led the Canadian Ophthalmological Society, in January 1974, to form a committee to study the incidence, types and causes of hockey eye injuries and to devise means of reducing such injuries. Retrospective and current studies were undertaken, and face protectors were tested. In both pilot studies, sticks were the commonest cause and the highest number of eye injuries was in players 11-15 years old. An average of 15% of all injured eyes were rendered legally blind. Cooperation with hockey authorities has resulted in changed rules and their sticter enforcement, and formulation of standards for face protection approved by the Canadian Standards Association. In this interim report the committee recommends that all amateur hockey players wear eye protectors and urges ophthalmologists to participate in efforts to improve the design of protective equipment. Images FIG. 1 PMID:1181024

  16. Eye movements when viewing advertisements

    PubMed Central

    Higgins, Emily; Leinenger, Mallorie; Rayner, Keith

    2013-01-01

    In this selective review, we examine key findings on eye movements when viewing advertisements. We begin with a brief, general introduction to the properties and neural underpinnings of saccadic eye movements. Next, we provide an overview of eye movement behavior during reading, scene perception, and visual search, since each of these activities is, at various times, involved in viewing ads. We then review the literature on eye movements when viewing print ads and warning labels (of the kind that appear on alcohol and tobacco ads), before turning to a consideration of advertisements in dynamic media (television and the Internet). Finally, we propose topics and methodological approaches that may prove to be useful in future research. PMID:24672500

  17. Along Endurance Crater's Inner Wall (Right Eye)

    NASA Technical Reports Server (NTRS)

    2004-01-01

    This view from the base of 'Burns Cliff' in the inner wall of 'Endurance Crater' combines several frames taken by Opportunity's navigation camera during the NASA rover's 280th martian day (Nov. 6, 2004). It is the right-eye member of a stereo pair, presented in a cylindrical-perspective projection with geometric seam correction. The cliff dominates the left and right portions of the image, while the central portion looks down into the crater. The 'U' shape of this mosaic results from the rover's tilt of about 30 degrees on the sloped ground below the cliff. Rover wheel tracks in the left half of the image show some of the slippage the rover experienced in making its way to this point. The site from which this image was taken has been designated as Opportunity's Site 37.

  18. Along Endurance Crater's Inner Wall (Left Eye)

    NASA Technical Reports Server (NTRS)

    2004-01-01

    This view from the base of 'Burns Cliff' in the inner wall of 'Endurance Crater' combines several frames taken by Opportunity's navigation camera during the NASA rover's 280th martian day (Nov. 6, 2004). It is the left-eye member of a stereo pair, presented in a cylindrical-perspective projection with geometric seam correction. The cliff dominates the left and right portions of the image, while the central portion looks down into the crater. The 'U' shape of this mosaic results from the rover's tilt of about 30 degrees on the sloped ground below the cliff. Rover wheel tracks in the left half of the image show some of the slippage the rover experienced in making its way to this point. The site from which this image was taken has been designated as Opportunity's Site 37.

  19. Six1 is a key regulator of the developmental and evolutionary architecture of sensory neurons in craniates

    PubMed Central

    2014-01-01

    Background Various senses and sensory nerve architectures of animals have evolved during adaptation to exploit diverse environments. In craniates, the trunk sensory system has evolved from simple mechanosensory neurons inside the spinal cord (intramedullary), called Rohon-Beard (RB) cells, to multimodal sensory neurons of dorsal root ganglia (DRG) outside the spinal cord (extramedullary). The fish and amphibian trunk sensory systems switch from RB cells to DRG during development, while amniotes rely exclusively on the DRG system. The mechanisms underlying the ontogenic switching and its link to phylogenetic transition remain unknown. Results In Xenopus, Six1 overexpression promoted precocious apoptosis of RB cells and emergence of extramedullary sensory neurons, whereas Six1 knockdown delayed the reduction in RB cell number. Genetic ablation of Six1 and Six4 in mice led to the appearance of intramedullary sensory neuron-like cells as a result of medial migration of neural crest cells into the spinal cord and production of immature DRG neurons and fused DRG. Restoration of SIX1 expression in the neural crest-linage partially rescued the phenotype, indicating the cell autonomous requirements of SIX1 for normal extramedullary sensory neurogenesis. Mouse Six1 enhancer that mediates the expression in DRG neurons activated transcription in Xenopus RB cells earlier than endogenous six1 expression, suggesting earlier onset of mouse SIX1 expression than Xenopus during sensory development. Conclusions The results indicated the critical role of Six1 in transition of RB cells to DRG neurons during Xenopus development and establishment of exclusive DRG system of mice. The study provided evidence that early appearance of SIX1 expression, which correlated with mouse Six1 enhancer, is essential for the formation of DRG-dominant system in mice, suggesting that heterochronic changes in Six1 enhancer sequence play an important role in alteration of trunk sensory architecture and contribute to the evolution of the trunk sensory system. PMID:24885223

  20. The Etiological Spectrum of Acute Sensory Myelitis

    PubMed Central

    Hyun, Jae-Won; Kim, Jee Young; Choi, Kyung Gyu; Kim, Ho Jin

    2015-01-01

    Background and Purpose Acute myelitis patients exhibiting only sensory deficits upon initial presentation are not commonly encountered in clinical practice, but they definitely exist. Since acute sensory myelitis has not been investigated previously, this study evaluated the etiological spectrum of the condition with the aim of describing the clinical characteristics thereof. Methods Patients with acute myelitis who presented at the Ewha Womans University Medical Center (during 1999-2012) and the National Cancer Center (during 2005-2014) with only sensory symptoms as first clinical features were enrolled in this study. Their medical records, electrophysiological and laboratory data, and MRI findings were analyzed retrospectively. Results Of a total of 341 acute myelitis patients, 52 (15%) were identified as having acute sensory myelitis. The male-to-female ratio of these patients was 35:17, and their age at the onset of the condition was 41.7±10.5 years (mean±SD; range, 24-72 years). Acute sensory myelitis developed in patients with multiple sclerosis (MS; 14%), neuromyelitis optica spectrum disorder (NMOSD; 17%), and acute myelitis associated with concurrent systemic diseases including Behçet's disease and cancer (6%). Despite detailed evaluation, the etiology of 33 patients with acute myelitis could not be determined. Longitudinally extensive transverse myelitis on spinal MRI and progression of the sensory level were observed most commonly in NMOSD patients (89% and 78%, respectively); however, these patients did not exhibit sensory dissociation. Residual negative sensory symptoms were observed more frequently in NMOSD patients (33%) than in those with acute myelitis of unknown cause (24%) or MS (14%). During the long-term follow-up (4.7±2.7 years) of patients who did not undergo maintenance immunotherapy, a monophasic clinical course was common in those with acute myelitis of unknown cause (76%), but not in NMOSD or MS patients. Conclusions Accurate identification of the diverse nature of acute sensory myelitis may assist in patient care. PMID:26174785

  1. Videoanalysis of involuntary eye movements

    NASA Astrophysics Data System (ADS)

    Skripal, Anatoli V.; Usanova, Tatjana B.; Abramov, Anton V.; Usanov, Dmitry A.

    2002-07-01

    The method for monitoring of involuntary eye motion on the basis of image processing and analysis technology is posed. The efficiency of the program for the object movement analysis by its trajectory and spectrum is demonstrated. The results of measuring of involuntary eye movements of patients with nystagmus are presented. The measuring results characterizing the nystagmus status changing before and after the squint correction is demonstrated.

  2. Eye-voice-controlled interface

    NASA Technical Reports Server (NTRS)

    Glenn, Floyd A., III; Iavecchia, Helene P.; Ross, Lorna V.; Stokes, James M.; Weiland, William J.

    1986-01-01

    The Ocular Attention-Sensing Interface System (OASIS) is an innovative human-computer interface which utilizes eye movement and voice commands to communicate messages between the operator and the system. This report initially describes some technical issues relevant to the development of such an interface. The results of preliminary experiments which evaluate alternative eye processing algorithms and feedback techniques are presented. Candidate interface applications are also discussed.

  3. Botanical origin, colour, granulation, and sensory properties of the Harenna forest honey, Bale, Ethiopia.

    PubMed

    Belay, Abera; Solomon, W K; Bultossa, Geremew; Adgaba, Nuru; Melaku, Samuel

    2015-01-15

    In this study, the Harenna forest honey samples were investigated with respect to their botanical origin, granulation, colour and sensory properties. Sixteen honey samples were collected from two representative sites (Chiri, C, and Wabero, W) using random sampling techniques. Botanical origin was investigated using qualitative pollen analysis by counting 500 pollen grains using harmonised methods of melissopalynology. Granulation, colour, and sensory properties of honey were determined by visual observation, using Pfund grader, acceptability and preference tests, respectively. Honey samples were also tested for tetracycline. Honey obtained from Wabero is originated dominantly from Syzygium guineense while Chiri was multifloral. The colour of honey ranged from 34 to 85 with light amber and extra light amber colours. The honey samples were free from tetracycline residue and form coarse granules slowly. Significant variation (p>0.05) in sensory preference and acceptability tests not observed due to hive types and locations. PMID:25148981

  4. [Specific cases of normo-sensorial strabismus: accommodative microstrabismus].

    PubMed

    Paris, V

    1999-01-01

    This study shows that, in a population of microstrabic patients (N = 76), a regain of a normal stereoscopy was possible in 19.6 of the cases (14 cases). Of these patients, 14 were hyperopic. With the full hyperopic correction, the angle of deviation on the alternate cover test was 0.45 PD (range: 0 to 3 PD). Without correction the deviation increased to between 3 PD and 10 PD (mean: 6.3 PD). Ten patients presented an anisometropia between 0.75 D to 2.50 D. (mean: 1.4 D). All anisometropic patients were hyperopic and hyperopia was higher in the dominated eye in all these cases. These results demonstrate the interest of the definition of microtropia as a specific strabismological entity, which can be congenital or acquired and be influenced by accommodative factors. The incidence of anisometropia, as a consequence rather than a cause of the pathological dominance is discussed. PMID:10546381

  5. Impact of crema on the aroma release and the in-mouth sensory perception of espresso coffee.

    PubMed

    Barron, D; Pineau, N; Matthey-Doret, W; Ali, S; Sudre, J; Germain, J C; Kolodziejczyk, E; Pollien, P; Labbe, D; Jarisch, C; Dugas, V; Hartmann, C; Folmer, B

    2012-09-01

    A set of six espresso coffees with different foam characteristics and similar above cup and in-mouth flavour sensory profiles was produced by combination of two varying parameters, the extraction pressure and the filtration of the coffee beverage. The coffees were subsequently evaluated in a comparative manner by a set of analytical (headspace, nose-space) and sensory (Temporal Dominance of Sensations) techniques. The presence of espresso crema in its standard quantity was demonstrated to be associated with the optimum release of pleasant high volatiles, both in the above cup headspace and in-mouth. On the other hand, the TDS study demonstrated that increasing amount of crema was associated with increasing roasted dominance along coffee consumption. Furthermore, a parallel was established between the roasted sensory dominance and the dominant release of 2-methylfuran in the nose-space. This was, however, an indirect link as 2-methylfuran was indeed a chemical marker of roasting but does not contribute to the roasted aroma. Lowering the standard amount of crema by filtration clearly decreased the release of pleasant high volatiles and the in-mouth roasted sensory dominance. On the other hand, increasing the usual crema volume by increasing the extraction pressure did not bring any added value concerning the above cup and in-mouth release of pleasant high volatiles. PMID:22706310

  6. Postural stability limits in manifest and premanifest Huntington's disease under different sensory conditions.

    PubMed

    Blanchet, M; Prince, F; Chouinard, S; Messier, J

    2014-10-24

    Increasing evidence indicates that Huntington's disease (HD) produces postural control impairments even before the clinical diagnosis. It has been suggested that postural disorders of HD patients are explained by deficits in the processing and integration of sensory information, but this hypothesis has been under-explored. In the present study, we evaluated the amplitude of the center of pressure (COP) displacement during maximum leaning in four directions (forward, backward, rightward and leftward) and under three sensory conditions (eyes open, eyes closed and eyes closed standing on foam). We assessed the stability limits in 20 individuals with a positive HD genetic test (12 premanifests; eight manifests HD) and 15 healthy controls. The COP displacements were analyzed during the first and second phases of maintenance of the maximum leaning position. Manifest HD patients showed significantly greater COP ranges than healthy controls in both learning phases and all sensory conditions, but the greatest deterioration of their performance was found in the foam condition. In contrast, premanifest HD patients displayed larger COP ranges than controls only during the second phase of maximum learning, especially in the foam condition. Furthermore, both HD groups had significantly smaller limits of stability than healthy subjects during the second phase of maximum learning. However, their ability to maintain the maximum leaning position was degraded during both learning phases. Together, these findings demonstrate that HD reduces the limits of stability even before the clinical disease onset. Furthermore, our results indicate that dynamic postural tasks with high demand for sensorimotor integration and especially the use of proprioception are highly sensitive to early HD disease processes. This dynamic postural task may become a useful biomarker of HD progression. PMID:25168735

  7. The Cat's Eye Nebula

    NASA Technical Reports Server (NTRS)

    1994-01-01

    This NASA Hubble Space Telescope image shows one of the most complex planetary nebulae ever seen, NGC 6543, nicknamed the 'Cat's Eye Nebula.' Hubble reveals surprisingly intricate structures including concentric gas shells, jets of high-speed gas and unusual shock-induced knots of gas. Estimated to be 1,000 years old, the nebula is a visual 'fossil record' of the dynamics and late evolution of a dying star. A preliminary interpretation suggests that the star might be a double-star system. The suspected companion star also might be responsible for a pair of high-speed jets of gas that lie at right angles to this equatorial ring. If the companion were pulling in material from a neighboring star, jets escaping along the companion's rotation axis could be produced. These jets would explain several puzzling features along the periphery of the gas lobes. Like a stream of water hitting a sand pile, the jets compress gas ahead of them, creating the 'curlicue' features and bright arcs near the outer edge of the lobes. The twin jets are now pointing in different directions than these features. This suggests the jets are wobbling, or precessing, and turning on and off episodically. This color picture, taken with the Wide Field Planetary Camera-2, is a composite of three images taken at different wavelengths. (red, hydrogen-alpha; blue, neutral oxygen, 6300 angstroms; green, ionized nitrogen, 6584 angstroms). The image was taken on September 18, 1994. NGC 6543 is 3,000 light- years away in the northern constellation Draco. The term planetary nebula is a misnomer; dying stars create these cocoons when they lose outer layers of gas. The process has nothing to do with planet formation, which is predicted to happen early in a star's life.

  8. Electromagnetic Characterization Of Metallic Sensory Alloy

    NASA Technical Reports Server (NTRS)

    Wincheski, Russell A.; Simpson, John; Wallace, Terryl A.; Newman, John A.; Leser, Paul; Lahue, Rob

    2012-01-01

    Ferromagnetic shape-memory alloy (FSMA) particles undergo changes in both electromagnetic properties and crystallographic structure when strained. When embedded in a structural material, these attributes can provide sensory output of the strain state of the structure. In this work, a detailed characterization of the electromagnetic properties of a FSMA under development for sensory applications is performed. In addition, a new eddy current probe is used to interrogate the electromagnetic properties of individual FSMA particles embedded in the sensory alloy during controlled fatigue tests on the multifunctional material.

  9. Sensory Plasticity in Human Motor Learning.

    PubMed

    Ostry, David J; Gribble, Paul L

    2016-02-01

    There is accumulating evidence from behavioral, neurophysiological, and neuroimaging studies that the acquisition of motor skills involves both perceptual and motor learning. Perceptual learning alters movements, motor learning, and motor networks of the brain. Motor learning changes perceptual function and the sensory circuits of the brain. Here, we review studies of both human limb movement and speech that indicate that plasticity in sensory and motor systems is reciprocally linked. Taken together, this points to an approach to motor learning in which perceptual learning and sensory plasticity have a fundamental role. PMID:26774345

  10. The eye and the heart

    PubMed Central

    Flammer, Josef; Konieczka, Katarzyna; Bruno, Rosa M.; Virdis, Agostino; Flammer, Andreas J.; Taddei, Stefano

    2013-01-01

    The vasculature of the eye and the heart share several common characteristics. The easily accessible vessels of the eye are therefore—to some extent—a window to the heart. There is interplay between cardiovascular functions and risk factors and the occurrence and progression of many eye diseases. In particular, arteriovenous nipping, narrowing of retinal arteries, and the dilatation of retinal veins are important signs of increased cardiovascular risk. The pressure in the dilated veins is often markedly increased due to a dysregulation of venous outflow from the eye. Besides such morphological criteria, functional alterations might be even more relevant and may play an important role in future diagnostics. Via neurovascular coupling, flickering light dilates capillaries and small arterioles, thus inducing endothelium-dependent, flow-mediated dilation of larger retinal vessels. Risk factors for arteriosclerosis, such as dyslipidaemia, diabetes, or systemic hypertension, are also risk factors for eye diseases such as retinal arterial or retinal vein occlusions, cataracts, age-related macular degeneration, and increases in intraocular pressure (IOP). Functional alterations of blood flow are particularly relevant to the eye. The primary vascular dysregulation syndrome (PVD), which often includes systemic hypotension, is associated with disturbed autoregulation of ocular blood flow (OBF). Fluctuation of IOP on a high level or blood pressure on a low level leads to instable OBF and oxygen supply and therefore to oxidative stress, which is particularly involved in the pathogenesis of glaucomatous neuropathy. Vascular dysregulation also leads to a barrier dysfunction and thereby to small retinal haemorrhages. PMID:23401492

  11. Simulation of Ametropic Human Eyes

    NASA Astrophysics Data System (ADS)

    Tan, Bo; Chen, Ying-Ling; Lewis, James W. L.

    2004-11-01

    The computational simulation of the performance of human eyes is complex because the optical parameters of the eye depend on many factors, including age, gender, race, refractive status (accommodation and near- or far-sightedness). This task is made more difficult by the inadequacy of the population statistical characteristics of these parameters. Previously we simulated ametropic (near- or far-sighted) eyes using three independent variables: the axial length of the eye, the corneal surface curvature, and the intraocular refractive index gradient. The prescription for the correction of an ametropic eye is determined by its second-order coefficients of the wavefront aberrations. These corrections are typically achieved using contact lens, spectacle lens, or laser surgery (LASIK). However, the higher order aberrations, which are not corrected and are likely complicated or enhanced by the lower-order correction, could be important for visual performance in a darkened environment. In this paper, we investigate the higher order wavefront aberrations of synthetic ametropic eyes and compare results with measured data published in the past decade. The behavior of three types of ametropes is discussed.

  12. Highly dominating, highly authoritarian personalities.

    PubMed

    Altemeyer, Bob

    2004-08-01

    The author considered the small part of the population whose members score highly on both the Social Dominance Orientation scale and the Right-Wing Authoritarianism scale. Studies of these High SDO-High RWAs, culled from samples of nearly 4000 Canadian university students and over 2600 of their parents and reported in the present article, reveal that these dominating authoritarians are among the most prejudiced persons in society. Furthermore, they seem to combine the worst elements of each kind of personality, being power-hungry, unsupportive of equality, manipulative, and amoral, as social dominators are in general, while also being religiously ethnocentric and dogmatic, as right-wing authoritarians tend to be. The author suggested that, although they are small in number, such persons can have considerable impact on society because they are well-positioned to become the leaders of prejudiced right-wing political movements. PMID:15279331

  13. Gravity-Induced Vacuum Dominance

    SciTech Connect

    Lima, William C. C.; Vanzella, Daniel A. T.

    2010-04-23

    It has been widely believed that, except in very extreme situations, the influence of gravity on quantum fields should amount to just small, subdominant contributions. This view seemed to be endorsed by the seminal results obtained over the last decades in the context of renormalization of quantum fields in curved spacetimes. Here, however, we argue that this belief is false by showing that there exist well-behaved spacetime evolutions where the vacuum energy density of free quantum fields is forced, by the very same background spacetime, to become dominant over any classical energy-density component. By estimating the time scale for the vacuum energy density to become dominant, and therefore for backreaction on the background spacetime to become important, we argue that this (infrared) vacuum dominance may bear unexpected astrophysical and cosmological implications.

  14. Rhodopsin-like proteins in planarian eye and auricle: detection and functional analysis

    PubMed

    Azuma; Shinozawa

    1998-05-01

    The presence of rhodopsin-like proteins in the eyes and auricles of the freshwater planarian Dugesia japonica was confirmed using anti-frog-rhodopsin rabbit IgG. The apparent relative molecular masses of these proteins were 65x10(3) and 62x10(3), and positive reactions to IgG were localized to the microvilli of the photoreceptor cells in the eyes and to the sensory cilia, rootlets and microvilli in the auricles. Eye- or head-excised planarians showed no negative phototaxis, whereas intact or auricle-excised planarians did. During regeneration in head-excised planarians, the appearance of rhodopsin-like proteins in the regenerating eyes corresponded to the recovery of negative phototaxis behaviour. Head or auricle excision enhanced asexual fission under continuous illumination. However, eye excision had no such effect. These results suggest that the rhodopsin-like proteins in the eyes work as photoreceptors for negative phototaxis behaviour and that, in the auricles, they are involved in asexual fission originating from the circadian rhythm. PMID:9547303

  15. Functional genomics identifies regulators of the phototransduction machinery in the Drosophila larval eye and adult ocelli.

    PubMed

    Mishra, Abhishek Kumar; Bargmann, Bastiaan O R; Tsachaki, Maria; Fritsch, Cornelia; Sprecher, Simon G

    2016-02-15

    Sensory perception of light is mediated by specialized Photoreceptor neurons (PRs) in the eye. During development all PRs are genetically determined to express a specific Rhodopsin (Rh) gene and genes mediating a functional phototransduction pathway. While the genetic and molecular mechanisms of PR development is well described in the adult compound eye, it remains unclear how the expression of Rhodopsins and the phototransduction cascade is regulated in other visual organs in Drosophila, such as the larval eye and adult ocelli. Using transcriptome analysis of larval PR-subtypes and ocellar PRs we identify and study new regulators required during PR differentiation or necessary for the expression of specific signaling molecules of the functional phototransduction pathway. We found that the transcription factor Krüppel (Kr) is enriched in the larval eye and controls PR differentiation by promoting Rh5 and Rh6 expression. We also identified Camta, Lola, Dve and Hazy as key genes acting during ocellar PR differentiation. Further we show that these transcriptional regulators control gene expression of the phototransduction cascade in both larval eye and adult ocelli. Our results show that PR cell type-specific transcriptome profiling is a powerful tool to identify key transcriptional regulators involved during several aspects of PR development and differentiation. Our findings greatly contribute to the understanding of how combinatorial action of key transcriptional regulators control PR development and the regulation of a functional phototransduction pathway in both larval eye and adult ocelli. PMID:26769100

  16. 14 CFR 67.303 - Eye.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 2 2011-01-01 2011-01-01 false Eye. 67.303 Section 67.303 Aeronautics and... AND CERTIFICATION Third-Class Airman Medical Certificate § 67.303 Eye. Eye standards for a third-class airman medical certificate are: (a) Distant visual acuity of 20/40 or better in each eye separately,...

  17. 14 CFR 67.103 - Eye.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 2 2010-01-01 2010-01-01 false Eye. 67.103 Section 67.103 Aeronautics and... AND CERTIFICATION First-Class Airman Medical Certificate § 67.103 Eye. Eye standards for a first-class airman medical certificate are: (a) Distant visual acuity of 20/20 or better in each eye separately,...

  18. 14 CFR 67.103 - Eye.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 2 2011-01-01 2011-01-01 false Eye. 67.103 Section 67.103 Aeronautics and... AND CERTIFICATION First-Class Airman Medical Certificate § 67.103 Eye. Eye standards for a first-class airman medical certificate are: (a) Distant visual acuity of 20/20 or better in each eye separately,...

  19. 21 CFR 878.4440 - Eye pad.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Eye pad. 878.4440 Section 878.4440 Food and Drugs... GENERAL AND PLASTIC SURGERY DEVICES Surgical Devices § 878.4440 Eye pad. (a) Identification. An eye pad is... use as a bandage over the eye for protection or absorption of secretions. (b) Classification. Class...

  20. 21 CFR 878.4440 - Eye pad.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Eye pad. 878.4440 Section 878.4440 Food and Drugs... GENERAL AND PLASTIC SURGERY DEVICES Surgical Devices § 878.4440 Eye pad. (a) Identification. An eye pad is... use as a bandage over the eye for protection or absorption of secretions. (b) Classification. Class...

  1. 14 CFR 67.303 - Eye.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 2 2010-01-01 2010-01-01 false Eye. 67.303 Section 67.303 Aeronautics and... AND CERTIFICATION Third-Class Airman Medical Certificate § 67.303 Eye. Eye standards for a third-class airman medical certificate are: (a) Distant visual acuity of 20/40 or better in each eye separately,...

  2. Contact Lens-Related Eye Infections

    MedlinePLUS

    ... D. Español Eye Health / Eye Health A-Z Contact Lens-Related Eye Infections Sections Contact Lens-Related ... About Contact Lenses Proper Care of Contact Lenses Contact Lens-Related Eye Infections Written by: Kierstan Boyd ...

  3. A Teaching Eye Model for Ophthalmoscopy.

    ERIC Educational Resources Information Center

    Miller, David

    1981-01-01

    A teaching eye model that allows the medical student to learn the hand-eye coordination and associated thinking patterns that allow for a more sophisticated use of the ophthalmoscope is described. The eye teaching model attempted to simulate the features found in the eye of a real patient. (MLW)

  4. Dominant resistance against plant viruses

    PubMed Central

    de Ronde, Dryas; Butterbach, Patrick; Kormelink, Richard

    2014-01-01

    To establish a successful infection plant viruses have to overcome a defense system composed of several layers. This review will overview the various strategies plants employ to combat viral infections with main emphasis on the current status of single dominant resistance (R) genes identified against plant viruses and the corresponding avirulence (Avr) genes identified so far. The most common models to explain the mode of action of dominant R genes will be presented. Finally, in brief the hypersensitive response (HR) and extreme resistance (ER), and the functional and structural similarity of R genes to sensors of innate immunity in mammalian cell systems will be described. PMID:25018765

  5. Motor-Related Signals in the Intraparietal Cortex Encode Locations in a Hybrid, rather than Eye-Centered Reference Frame

    PubMed Central

    Mullette-Gillman, O'Dhaniel A.; Cohen, Yale E.

    2009-01-01

    The reference frame used by intraparietal cortex neurons to encode locations is controversial. Many previous studies have suggested eye-centered coding, whereas we have reported that visual and auditory signals employ a hybrid reference frame (i.e., a combination of head- and eye-centered information) (Mullette-Gillman et al. 2005). One possible explanation for this discrepancy is that sensory-related activity, which we studied previously, is hybrid, whereas motor-related activity might be eye centered. Here, we examined the reference frame of visual and auditory saccade-related activity in the lateral and medial banks of the intraparietal sulcus (areas lateral intraparietal area [LIP] and medial intraparietal area [MIP]) of 2 rhesus monkeys. We recorded from 275 single neurons as monkeys performed visual and auditory saccades from different initial eye positions. We found that both visual and auditory signals reflected a hybrid of head- and eye-centered coordinates during both target and perisaccadic task periods rather than shifting to an eye-centered format as the saccade approached. This account differs from numerous previous recording studies. We suggest that the geometry of the receptive field sampling in prior studies was biased in favor of an eye-centered reference frame. Consequently, the overall hybrid nature of the reference frame was overlooked because the non–eye-centered response patterns were not fully characterized. PMID:19068491

  6. Goiter and Laryngeal Sensory Neuropathy

    PubMed Central

    Hamdan, Abdul Latif; Jabour, Jad; Azar, Sami T.

    2013-01-01

    Objective. Examining the prevalence of laryngeal sensory neuropathy (LSN) in goiter patients versus a control group. Study Design. Cross-sectional study. Methods. 33 Goiter patients were enrolled versus 25 age-matched controls. TSH levels, size of thyroid gland, and presence or absence of thyroid nodules were reported. Subjects were asked about the presence or absence of any of the following symptoms: cough, globus pharyngeus, and/or throat clearing that persistented for more than 6 weeks. The presence of one or more of these symptoms for at least six weeks in the absence of LPRD, allergy, asthma, ACE inhibitor intake, and psychogenic disorder was defined as LSN. Results. For goitrous patients mean age (years) was (41.73 ± 9.47) versus (37.44 ± 10.89) for controls. 82% goitrous patients had known nodules and 27% carried a simultaneous diagnosis of hypothyroidism. Among those with documented size (61%), mean total thyroid volume was 26.996 ± 14.852 cm3, with a range from 9.430 to 67.022 cm3. The overall prevalence of LSN among goitrous patients was 42% versus 12% among controls (P = 0.0187). There was no correlation between LSN, size of thyroid gland, and TSH level. Conclusion. The prevalence of LSN in goitrous patients is significantly higher than that in a nongoitrous population. PMID:23818901

  7. Ocular Dominance Is Associated with the Ganglion Cell-Inner Plexiform Layer Thickness Profile in the Macula

    PubMed Central

    Choi, Jin A.; Kim, Jung-Sub; Jeong, Hyun Jin; Lee, Jin Ah; Park, Chan Kee

    2016-01-01

    Purpose To investigate the characteristics of macular ganglion cell-inner plexiform layer (GCIPL) thickness profiles associated with ocular dominance. Setting Private practice, Seoul, Republic of Korea. Design Comparative case-control study. Methods Both eyes of 199 participants with no ophthalmic abnormalities were included. Participants were imaged by spectral-domain optical coherence tomography, and underwent dominant eye testing using a hole-in-a-card test (sighting dominance) at the same visit. Macular GCIPL, as well as circumpapillary retinal nerve fiber layer (RNFL) thickness were compared for individual patients, according to ocular dominance. Results Ocular dominance occurred predominantly in the right eye (right vs. left: 72.36 vs. 27.60%; P < 0.001). In the comparison of macular GCIPL thickness, the average (81.27±5.01 μm vs. 80.66±6.31 μm in dominant vs. non-dominant eyes), inferonasal (81.39±5.47μm vs. 80.33±6.82μm, and inferior sectors (77.95±6.05μm vs. 76.97±8.15μm) were significantly different between dominant and non-dominant eyes (P = 0.040, 0.005, and 0.032, respectively). Significant predictors of average GCIPL thickness were spherical equivalent (β = 1.37, P<0.001), astigmatic power (β = 1.44, P = 0.009), disc area (β = 3.90, P < 0.001), average RNFL thickness (β = 0.22, P<0.001), average cup-to-disc ratio (β = 5.74, P = 0.002), difference between the inferior and superior quadrant RNFL thicknesses (β = 0.08, P = 0.024), and ocular dominance (β = 2.10, P = 0.020). On multivariate regression analysis, ocular dominance was correlated with average GCIPL thickness after adjusting for potential confounders (β = 1.63, P = 0.048). Conclusions Dominant eyes accompanied significantly thicker average macular GCIPL. This information suggests that macular GCIPL thickness may provide an indicator of the relative dominance of an eye. PMID:26918335

  8. Analytical methods for chemical and sensory characterization of scent-markings in large wild mammals: a review.

    PubMed

    Soso, Simone B; Koziel, Jacek A; Johnson, Anna; Lee, Young Jin; Fairbanks, W Sue

    2014-01-01

    In conjoining the disciplines of "ethology" and "chemistry" the field of "Ethochemistry" has been instituted. Ethochemistry is an effective tool in conservation efforts of endangered species and the understanding of behavioral patterns across all species. Chemical constituents of scent-markings have an important, yet poorly understood function in territoriality, reproduction, dominance, and impact on evolutionary biology, especially in large mammals. Particular attention has recently been focused on scent-marking analysis of great cats (Kalahari leopards (Panthera pardus), puma (Puma concolor) snow leopard (Panthera uncia), African lions (Panthera leo), cheetahs (Acinonyx jubatus), and tigers (Panthera tigris)) for the purpose of conservation. Sensory analyses of scent-markings could address knowledge gaps in ethochemistry. The objective of this review is to summarize the current state-of-the art of both the chemical and sensory analyses of scent-markings in wild mammals. Specific focus is placed on sampling and sample preparation, chemical analysis, sensory analysis, and simultaneous chemical and sensory analyses. Constituents of exocrine and endocrine secretions have been most commonly studied with chromatography-based analytical separations. Odor analysis of scent-markings provides an insight into the animal's sensory perception. A limited number of articles have been published in the area of sensory characterization of scent marks. Simultaneous chemical and sensory analyses with chromatography-olfactometry hyphenation could potentially aid conservation efforts by linking perceived odor, compounds responsible for odor, and resulting behavior. PMID:24603639

  9. Analytical Methods for Chemical and Sensory Characterization of Scent-Markings in Large Wild Mammals: A Review

    PubMed Central

    Soso, Simone B.; Koziel, Jacek A.; Johnson, Anna; Lee, Young Jin; Fairbanks, W. Sue

    2014-01-01

    In conjoining the disciplines of “ethology” and “chemistry” the field of “Ethochemistry” has been instituted. Ethochemistry is an effective tool in conservation efforts of endangered species and the understanding of behavioral patterns across all species. Chemical constituents of scent-markings have an important, yet poorly understood function in territoriality, reproduction, dominance, and impact on evolutionary biology, especially in large mammals. Particular attention has recently been focused on scent-marking analysis of great cats (Kalahari leopards (Panthera pardus), puma (Puma concolor) snow leopard (Panthera uncia), African lions (Panthera leo), cheetahs (Acinonyx jubatus), and tigers (Panthera tigris)) for the purpose of conservation. Sensory analyses of scent-markings could address knowledge gaps in ethochemistry. The objective of this review is to summarize the current state-of-the art of both the chemical and sensory analyses of scent-markings in wild mammals. Specific focus is placed on sampling and sample preparation, chemical analysis, sensory analysis, and simultaneous chemical and sensory analyses. Constituents of exocrine and endocrine secretions have been most commonly studied with chromatography-based analytical separations. Odor analysis of scent-markings provides an insight into the animal's sensory perception. A limited number of articles have been published in the area of sensory characterization of scent marks. Simultaneous chemical and sensory analyses with chromatography-olfactometry hyphenation could potentially aid conservation efforts by linking perceived odor, compounds responsible for odor, and resulting behavior. PMID:24603639

  10. Chromosomal localization and genomic organization of genes encoding guanylyl cyclase receptors expressed in olfactory sensory neurons and retina

    SciTech Connect

    Yang, Ruey-Bing; Fuelle, H.J.; Garbers, D.L.

    1996-02-01

    We recently cloned three membrane guanylyl cyclases, designated GC-D, CG-E, and GC-F, from rat olfactory tissue and eye. Amino acid sequence homology suggests that they may compose a new gene subfamily of guanylyl cyclase receptors specifically expressed in sensory tissues. Their chromosomal localization was determined by mouse interspecific backcross analysis. The GC-D, CG-E, and GC-F genes (Gucy2d, Gucy2e, and Gucy2f) are dispersed through the mouse genome in that they map to chromosomes 7, 11, and X, respectively. Close proximity of the mouse GC-D gene to Omp (olfactory marker protein) and Hbb (hemoglobin {beta}-chain complex) suggests that the human homolog gene maps to 11p15.4 or 11q13.4-q14.1. The human GC-F gene was localized to the long arm of chromosome Xq22 by fluorescence in situ hybridization. The genomic organization of the mouse GC-E, and GC-F genomic clones contain identical exon-intron boundaries within their extracellular and cytoplasmic domains, demonstrating the conservation of the gene structures. With respect to human genetic diseases, GC-E mapped to mouse chromosome 11 within a syntenic region on human chromosome 17p13 that has been linked with loci for autosomal dominant retinitis pigmentosa and Leber congenital amaurosis. No apparent disease loci have been yet linked to the locations of the GC-D or GC-F genes. 39 refs., 3 figs., 2 tabs.

  11. When the Wheels Touch Earth and the Flight is Through, Pilots Find One Eye is Better Than Two?

    NASA Technical Reports Server (NTRS)

    Valimont, Brian; Wise, John A.; Nichols, Troy; Best, Carl; Suddreth, John; Cupero, Frank

    2009-01-01

    This study investigated the impact of near to eye displays on both operational and visual performance by employing a human-in-the-loop simulation of straight-in ILS approaches while using a near to eye (NTE) display. The approaches were flown in simulated visual and instrument conditions while using either a biocular NTE or a monocular NTE display on either the dominant or non dominant eye. The pilot s flight performance, visual acuity, and ability to detect unsafe conditions on the runway were tested.

  12. New Solutions for Synchronized Domineering

    NASA Astrophysics Data System (ADS)

    Bahri, Sahil; Kruskal, Clyde P.

    Cincotti and Iida invented the game of Synchronized Domineering, and analyzed a few special cases. We develop a more general technique of analysis, and obtain results for many more special cases. We obtain complete results for board sizes 3 ×n, 5 ×n, 7 ×n, and 9 ×n (for n large enough) and partial results for board sizes 2×n, 4 ×n, and 6 ×n.

  13. Dominance and Age in Bilingualism

    ERIC Educational Resources Information Center

    Birdsong, David

    2014-01-01

    The present article examines the relationship between age and dominance in bilingual populations. Age in bilingualism is understood as the point in development at which second language (L2) acquisition begins and as the chronological age of users of two languages. Age of acquisition (AoA) is a factor in determining which of a bilingual's two…

  14. Brutus Dominance Behavior After Capture

    USGS Multimedia Gallery

    A couple of hours after being immobilized for collaring, Brutus, a wolf being studied by USGS scientists, appears to have fully recovered. He returns to his pack mates and demonstrates dominance behavior over a younger male wolf. Note that Brutus has a stiff, aggressive stance and upright tail, whil...

  15. Dominance and Age in Bilingualism

    ERIC Educational Resources Information Center

    Birdsong, David

    2014-01-01

    The present article examines the relationship between age and dominance in bilingual populations. Age in bilingualism is understood as the point in development at which second language (L2) acquisition begins and as the chronological age of users of two languages. Age of acquisition (AoA) is a factor in determining which of a bilingual's two…

  16. Specialized Cilia in Mammalian Sensory Systems

    PubMed Central

    Falk, Nathalie; Lösl, Marlene; Schröder, Nadja; Gießl, Andreas

    2015-01-01

    Cilia and flagella are highly conserved and important microtubule-based organelles that project from the surface of eukaryotic cells and act as antennae to sense extracellular signals. Moreover, cilia have emerged as key players in numerous physiological, developmental, and sensory processes such as hearing, olfaction, and photoreception. Genetic defects in ciliary proteins responsible for cilia formation, maintenance, or function underlie a wide array of human diseases like deafness, anosmia, and retinal degeneration in sensory systems. Impairment of more than one sensory organ results in numerous syndromic ciliary disorders like the autosomal recessive genetic diseases Bardet-Biedl and Usher syndrome. Here we describe the structure and distinct functional roles of cilia in sensory organs like the inner ear, the olfactory epithelium, and the retina of the mouse. The spectrum of ciliary function in fundamental cellular processes highlights the importance of elucidating ciliopathy-related proteins in order to find novel potential therapies. PMID:26378583

  17. Psychometric Validation of the Sensory Experiences Questionnaire

    PubMed Central

    Little, Lauren M.; Freuler, Ashley C.; Houser, Marisa B.; Guckian, Lisa; Carbine, Kristin; David, Fabian J.; Baranek, Grace T.

    2011-01-01

    INTRODUCTION We evaluated the psychometric properties of the Sensory Experiences Questionnaire (Version 1; Baranek, David, Poe, Stone, & Watson 2006), a brief caregiver questionnaire for young children with autismand developmental delays used to identify sensory processing patterns in the context of daily activities. METHOD Caregiver questionnaires (N = 358) were analyzed to determine internal consistency. The test–retest subsample (n = 24) completed two assessments within 2–4 wk. Internal consistency and test–retest reliability were analyzed using Cronbach’s coefficient ? and intraclass correlation coefficients, respectively. RESULTS Internal consistency for the SEQ was ? = .80. Test–retest reliability for the total score was excellent, with ICC = .92. DISCUSSION The SEQ is an internally consistent and reliable caregiver report measure of young children’s sensory processing patterns of hypo- and hyperresponsiveness. The SEQ can be used as an early tool for identifying sensory patterns in young children with autism and other developmental disabilities. PMID:21476368

  18. Specialized Cilia in Mammalian Sensory Systems.

    PubMed

    Falk, Nathalie; Lösl, Marlene; Schröder, Nadja; Gießl, Andreas

    2015-01-01

    Cilia and flagella are highly conserved and important microtubule-based organelles that project from the surface of eukaryotic cells and act as antennae to sense extracellular signals. Moreover, cilia have emerged as key players in numerous physiological, developmental, and sensory processes such as hearing, olfaction, and photoreception. Genetic defects in ciliary proteins responsible for cilia formation, maintenance, or function underlie a wide array of human diseases like deafness, anosmia, and retinal degeneration in sensory systems. Impairment of more than one sensory organ results in numerous syndromic ciliary disorders like the autosomal recessive genetic diseases Bardet-Biedl and Usher syndrome. Here we describe the structure and distinct functional roles of cilia in sensory organs like the inner ear, the olfactory epithelium, and the retina of the mouse. The spectrum of ciliary function in fundamental cellular processes highlights the importance of elucidating ciliopathy-related proteins in order to find novel potential therapies. PMID:26378583

  19. Peripapillary Retinoschisis in Glaucomatous Eyes

    PubMed Central

    Lee, Eun Ji; Kim, Tae-Woo; Kim, Mijin; Choi, Yun Jeong

    2014-01-01

    Purpose To investigate the structural and clinical characteristics of peripapillary retinoschisis observed in glaucomatous eyes using spectral-domain optical coherence tomography (SD-OCT). Methods Circumpapillary retinal nerve fiber layer (cpRNFL) and macular cross-hair SD-OCT scans and infrared fundus images of the glaucoma patients from the Investigating Glaucoma Progression Study (IGPS) and healthy volunteers were reviewed. Optic disc images obtained using enhanced depth imaging (EDI) SD-OCT were also evaluated. The structural characteristics and clinical course of the retinoschisis associated with glaucoma were investigated. Results Twenty-five retinoschisis areas were found in 22 of the 372 patients (5.9%) included in the IGPS, and in 1 area in 1 of 187 healthy control subjects (0.5%). In the 22 glaucomatous eyes with retinoschisis, the schisis was attached to the optic disc and overlapped with the retinal nerve fiber layer (RNFL) defect. The RNFL was the layer most commonly affected by the retinoschisis, either alone or together with other deeper layers. Acquired optic disc pit was identified in 8 eyes on disc photography and/or B-scan images obtained by EDI SD-OCT. Spontaneous resolution of this condition was observed in nine eyes. No retinal detachment or macular involvement of the retinoschisis was observed in any of the eyes. Multivariate analysis showed a significant influence of a higher intraocular pressure at SD-OCT scanning on the presence of retinoschisis (Odds ratio  = 1.418, P = 0.001). Conclusions The present study investigated 22 cases of peripapillary retinoschisis in glaucomatous eyes. The retinoschisis was attached to the optic nerve and topographically correlated with RNFL defect. It often resolved spontaneously without causing severe visual disturbance. Care should be taken not to overestimate the RNFL thickness in eyes with retinoschisis, and also not to misinterpret the resolution of retinoschisis as a rapid glaucomatous RNFL deterioration. PMID:24587238

  20. Evidence for sensory neuropathy and pharmacologic management.

    PubMed

    Greene, Scott M; Simpson, C Blake

    2010-02-01

    Recent literature points to postviral sensory neuropathy as a possible cause for refractory chronic cough. Vagal neuropathy may affect the sensory branches, inducing chronic cough or laryngospasm. Although the clinical presentation is fairly well described, there is little in the way of diagnostic criteria to establish this diagnosis. This article highlights the clinical picture of this disease and the efficacy, side-effect profiles of the currently used pharmacological interventions. PMID:20172257

  1. A layered network model of sensory cortex

    SciTech Connect

    Travis, B.J.

    1986-01-01

    An integrated computational approach to modeling sensory systems which couples realistic layered neural models of sensory cortex and midbrain nuclei to detailed models of the sense organs (e.g., retina or cochlea) is described. The approach is applied to the auditory system. Through an exercise of the model, it is shown that spatial location of sounds may be a natural consequence of the way cochlear response is mapped onto the cortex. 31 refs., 23 figs., 3 tabs.

  2. Sensory Processing in Adults with Autism Spectrum Disorders

    ERIC Educational Resources Information Center

    Crane, Laura; Goddard, Lorna; Pring, Linda

    2009-01-01

    Unusual sensory processing has been widely reported in autism spectrum disorders (ASDs); however, the majority of research in this area has focused on children. The present study assessed sensory processing in adults with ASD using the Adult/Adolescent Sensory Profile (AASP), a 60-item self-report questionnaire assessing levels of sensory…

  3. 38 CFR 17.149 - Sensori-neural aids.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 38 Pensions, Bonuses, and Veterans' Relief 1 2013-07-01 2013-07-01 false Sensori-neural aids. 17... Prosthetic, Sensory, and Rehabilitative Aids § 17.149 Sensori-neural aids. (a) Notwithstanding any other provision of this part, VA will furnish needed sensori-neural aids (i.e., eyeglasses, contact...

  4. 38 CFR 17.149 - Sensori-neural aids.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 38 Pensions, Bonuses, and Veterans' Relief 1 2014-07-01 2014-07-01 false Sensori-neural aids. 17... Prosthetic, Sensory, and Rehabilitative Aids § 17.149 Sensori-neural aids. (a) Notwithstanding any other provision of this part, VA will furnish needed sensori-neural aids (i.e., eyeglasses, contact...

  5. 38 CFR 17.149 - Sensori-neural aids.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 38 Pensions, Bonuses, and Veterans' Relief 1 2010-07-01 2010-07-01 false Sensori-neural aids. 17... Prosthetic, Sensory, and Rehabilitative Aids § 17.149 Sensori-neural aids. (a) Notwithstanding any other provision of this part, VA will furnish needed sensori-neural aids (i.e., eyeglasses, contact...

  6. 38 CFR 17.149 - Sensori-neural aids.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 38 Pensions, Bonuses, and Veterans' Relief 1 2011-07-01 2011-07-01 false Sensori-neural aids. 17... Prosthetic, Sensory, and Rehabilitative Aids § 17.149 Sensori-neural aids. (a) Notwithstanding any other provision of this part, VA will furnish needed sensori-neural aids (i.e., eyeglasses, contact...

  7. 38 CFR 17.149 - Sensori-neural aids.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 38 Pensions, Bonuses, and Veterans' Relief 1 2012-07-01 2012-07-01 false Sensori-neural aids. 17... Prosthetic, Sensory, and Rehabilitative Aids § 17.149 Sensori-neural aids. (a) Notwithstanding any other provision of this part, VA will furnish needed sensori-neural aids (i.e., eyeglasses, contact...

  8. Sensory Pedagogy: Understanding and Encountering Children through the Senses

    ERIC Educational Resources Information Center

    Johansson, Eva; Løkken, Gunvor

    2014-01-01

    In the present article we aim to explore the link between Merleau-Pontyan phenomenology and what we call sensory pedagogy. The latter connects to recent sensory ethnography as presented by S. Pink ("Sensory ethnography." London: Sage; 2009). We discuss how these thoughts can be put to work in toddler pedagogy. This kind of sensory…

  9. Anthropogenic noise affects behavior across sensory modalities.

    PubMed

    Kunc, Hansjoerg P; Lyons, Gillian N; Sigwart, Julia D; McLaughlin, Kirsty E; Houghton, Jonathan D R

    2014-10-01

    Many species are currently experiencing anthropogenically driven environmental changes. Among these changes, increasing noise levels are specifically a problem for species using acoustic signals (i.e., species relying on signals that use the same sensory modality as anthropogenic noise). Yet many species use other sensory modalities, such as visual and olfactory signals, to communicate. However, we have only little understanding of whether changes in the acoustic environment affect species that use sensory modalities other than acoustic signals. We studied the impact of anthropogenic noise on the common cuttlefish Sepia officinalis, which uses highly complex visual signals. We showed that cuttlefish adjusted their visual displays by changing their color more frequently during a playback of anthropogenic noise, compared with before and after the playback. Our results provide experimental evidence that anthropogenic noise has a marked effect on the behavior of species that are not reliant on acoustic communication. Thus, interference in one sensory channel, in this case the acoustic one, affects signaling in other sensory channels. By considering sensory channels in isolation, we risk overlooking the broader implications of environmental changes for the behavior of animals. PMID:25226190

  10. Indications for eye removal surgeries

    PubMed Central

    Koylu, Mehmet T.; Gokce, Gokcen; Uysal, Yusuf; Ceylan, Osman M.; Akıncıoglu, Dorukcan; Gunal, Armagan

    2015-01-01

    Objectives: To analyze the indications and types of eye removals at a military tertiary care hospital in Turkey. Methods: The medical records (age, gender, affected eye, type of surgical procedure, indications of surgery) of 123 patients who underwent evisceration and enucleation in the course of a 15-year period (January 2000 to December 2014) at Gulhane Military Medical Academy, Ankara, Turkey were reviewed retrospectively. Results: The mean age was 35.61±18.52 (range 3-80 years). The number of male in the patient group was 92 (74.8%) and female was 31 (25.2%). Patients who underwent evisceration were 95 (77.2%), whereas 28 (22.8%) of them underwent enucleation. The mean age of the eviscerated patients was 30.63±13.08, whereas the mean age of the enucleated patients was 52.50±23.92 (p<0.001). The leading indications for eye amputations were trauma (n=62, 50.4%), malignancy (n=20, 16.3%), painful blind eye and absolute glaucoma (n=20, 16.3%), endophthalmitis (n=12, 9.7%), and phthisis bulbi, and cosmetic reasons (n=9, 7.3%). Conclusion: Trauma was the most common etiology for evisceration, and malignancy was the most common etiology for enucleation. Using protective eyewear and early detection of intraocular malignancy and glaucoma through routine ophthalmic examinations are essential for providing non-invasive treatment modalities instead of eye removal. PMID:26446332

  11. How flies clean their eyes

    NASA Astrophysics Data System (ADS)

    Amador, Guillermo; Durand, Fabien; Mao, Wenbin; Alexeev, Alexander; Hu, David

    2013-11-01

    Flying insects face a barrage of foreign particles such as dust and pollen, which threaten to coat the insect's eyes and antennae, limiting their sensing abilities. In this study, we elucidate novel aerodynamic and elastic mechanisms by which insects keep these organs clean. The compound eye of many species of insects is covered by an array of short bristles, or setae, evenly spaced between each photoreceptor unit. Among these insect species, setae length is triple their spacing. We conduct numerical simulations and wind tunnel experiments using an insect eye mimic to show this critical setae length reduces shear rate at the eye surface by 80%. Thus, the setae create a stagnant zone in front of the eye, which diverts airflow to reduce deposition of particles. Setae can also act as springboards to catapult accumulated particles. In high speed videography of insects using their legs to clean themselves, we observe deflected setae hurling micron scale particles at accelerations over 100 times earth's gravity. The dual abilities of setae to divert airflow and catapult particles may motivate bio-inspired designs for dust-controlling lenses, sensors, and solar panels.

  12. Allergic conjunctivitis and dry eye.

    PubMed Central

    Fujishima, H; Toda, I; Shimazaki, J; Tsubota, K

    1996-01-01

    AIMS: Differential diagnosis of allergic conjunctivitis or dry eye is sometimes very difficult to diagnose by symptoms and clinical examination alone, especially in older patients. It was hypothesised that clinically allergic patients who were serum antigen specific IgE negative were candidates for dry eye. METHODS: Sixty patients were studied prospectively who were clinically diagnosed with allergic conjunctivitis by their itchy sensation and papilla formation of conjunctiva. They consisted of 30 serum antigen specific IgE positive and 30 IgE negative patients, with no significant differences in age. Dry eye examination and serum total IgE were performed on these two groups. RESULTS: No significant differences were seen between the two groups with regard to age (p = 0.76) and sex ratio. The antibody negative group had lower Schirmer's test scores (p = 0.002), lower tear clearance (p = 0.0001), lower tear function index (p = 0.0001), and lower serum total IgE (p = 0.04) than the antibody positive group. CONCLUSION: This study suggests that the evaluation of serum antigen specific IgE and tear dynamics are important for the differential diagnosis of patients with allergic conjunctivitis and dry eye. Clinically diagnosed allergic conjunctivitis with negative serum antigen specific and total IgE can be one form of dry eye. PMID:8976728

  13. Investment in sensory structures, testis size, and wing coloration in males of a diurnal moth species: trade-offs or correlated growth?

    PubMed

    Shiel, Brett P; Sherman, Craig D H; Elgar, Mark A; Johnson, Tamara L; Symonds, Matthew R E

    2015-04-01

    For dioecious animals, reproductive success typically involves an exchange between the sexes of signals that provide information about mate location and quality. Typically, the elaborate, secondary sexual ornaments of males signal their quality, while females may signal their location and receptivity. In theory, the receptor structures that receive the latter signals may also become elaborate or enlarged in a way that ultimately functions to enhance mating success through improved mate location. The large, elaborate antennae of many male moths are one such sensory structure, and eye size may also be important in diurnal moths. Investment in these traits may be costly, resulting in trade-offs among different traits associated with mate location. For polyandrous species, such trade-offs may also include traits associated with paternity success, such as larger testes. Conversely, we would not expect this to be the case for monandrous species, where sperm competition is unlikely. We investigated these ideas by evaluating the relationship between investment in sensory structures (antennae, eye), testis, and a putative warning signal (orange hindwing patch) in field-caught males of the monandrous diurnal painted apple moth Teia anartoides (Lepidoptera: Lymantriidae) in southeastern Australia. As predicted for a monandrous species, we found no evidence that male moths with larger sensory structures had reduced investment in testis size. However, contrary to expectation, investment in sensory structures was correlated: males with relatively larger antennae also had relatively larger eyes. Intriguingly, also, the size of male orange hindwing patches was positively correlated with testis size. PMID:25937904

  14. Investment in sensory structures, testis size, and wing coloration in males of a diurnal moth species: trade-offs or correlated growth?

    PubMed Central

    Shiel, Brett P; Sherman, Craig D H; Elgar, Mark A; Johnson, Tamara L; Symonds, Matthew R E

    2015-01-01

    For dioecious animals, reproductive success typically involves an exchange between the sexes of signals that provide information about mate location and quality. Typically, the elaborate, secondary sexual ornaments of males signal their quality, while females may signal their location and receptivity. In theory, the receptor structures that receive the latter signals may also become elaborate or enlarged in a way that ultimately functions to enhance mating success through improved mate location. The large, elaborate antennae of many male moths are one such sensory structure, and eye size may also be important in diurnal moths. Investment in these traits may be costly, resulting in trade-offs among different traits associated with mate location. For polyandrous species, such trade-offs may also include traits associated with paternity success, such as larger testes. Conversely, we would not expect this to be the case for monandrous species, where sperm competition is unlikely. We investigated these ideas by evaluating the relationship between investment in sensory structures (antennae, eye), testis, and a putative warning signal (orange hindwing patch) in field-caught males of the monandrous diurnal painted apple moth Teia anartoides (Lepidoptera: Lymantriidae) in southeastern Australia. As predicted for a monandrous species, we found no evidence that male moths with larger sensory structures had reduced investment in testis size. However, contrary to expectation, investment in sensory structures was correlated: males with relatively larger antennae also had relatively larger eyes. Intriguingly, also, the size of male orange hindwing patches was positively correlated with testis size. PMID:25937904

  15. Distal attribution and distance perception in sensory substitution

    PubMed Central

    Siegle, Joshua H.; Warren, William H.

    2013-01-01

    In sensory substitution, the user may be directly aware of distal objects, as in everyday perception, or make explicit cognitive inferences based on an awareness of the proximal stimulation. Anecdotal evidence supports the experience of distal attribution, but so far there have been few rigorous experimental tests of the claim. In this study, blindfolded participants observed a target light using a device consisting of a finger-mounted photodiode that drives tactile vibration on the back. With the blindfold off and the target removed, participants moved a reference object to match the perceived egocentric distance of the target. Participants who were instructed to attend to the distal target improved significantly during two hours of practice, whereas those instructed to attend to proximal variables showed no improvement. Unsigned error increased with ratings of proximal attention but decreased with ratings of target object solidity, consistent with distal attribution. Performance transferred to the non-dominant arm and to a rotated body orientation, demonstrating that learning did not depend on a joint-specific sensorimotor relationship between target distance and arm configuration. The results experimentally confirm that distal attribution can occur in sensory substitution, based on a perceptual strategy rather than an explicit cognitive strategy. Moreover, they suggest that the informational basis for distal attribution is not a joint-specific sensorimotor relation, but a more abstract spatial invariant. PMID:20402243

  16. Eye-Eye with Dr. Rachel Bishop | NIH MedlinePlus the Magazine

    MedlinePLUS

    ... this page please turn JavaScript on. Feature: Glaucoma Eye-to-Eye with Dr. Rachel Bishop Past Issues / Spring 2015 ... new patient comes in because they scratched their eye while working in the yard, or they think ...

  17. Videos from the National Eye Institute: Eye Diseases | NIH MedlinePlus the Magazine

    MedlinePLUS

    ... this page please turn Javascript on. Feature: Vision Videos from the National Eye Institute: Eye Diseases Past ... the early detection of eye disease. Share these videos with friends, family and colleagues. www.nei.nih. ...

  18. Frontal eye field neurons signal changes in decision criteria.

    PubMed

    Ferrera, Vincent P; Yanike, Marianna; Cassanello, Carlos

    2009-11-01

    Flexible links between sensory stimuli and behavioral responses underlie many cognitive processes. One process that contributes to flexible decision-making is categorization. Some categories are innate or overlearned, but, in many cases, category boundaries represent flexible decision criteria that can shift on the fly to adapt to changes in the environment. The ability to shift category boundaries allows decision-making to adapt to changing circumstances. We found that monkeys were able to switch rapidly between two category boundaries when classifying the speed of a moving dot pattern and that neurons in monkey frontal eye field (FEF) changed their activity when the boundary changed. The responses of a subpopulation of FEF neurons that were sensitive to both stimulus and boundary speed were used to classify the stimuli as accurately as the monkeys' performance. PMID:19855389

  19. A meme's eye view of speech-language pathology.

    PubMed

    Kamhi, Alan G

    2004-04-01

    In this article, the reason why certain terms, labels, and ideas prevail, whereas others fail to gain acceptance, will be considered. Borrowing the concept of "meme" from the study of evolution of ideas, it will be clear why language-based and phonological disorders have less widespread appeal than, for example, auditory processing and sensory integration disorders. Discussion will also center on why most speech-language pathologists refer to themselves as speech therapists or speech pathologists, and why it is more desirable to have dyslexia than to have a reading disability. In a meme's eye view, science and logic do not always win out because selection favors ideas (memes) that are easy to understand, remember, and copy. An unfortunate consequence of these selection forces is that successful memes typically provide superficially plausible answers for complex questions. PMID:15191323

  20. Mosaic: a position-effect variegation eye-color mutant in the mosquito Anopheles gambiae.

    PubMed

    Benedict, M Q; McNitt, L M; Cornel, A J; Collins, F H

    2000-01-01

    The Mosaic (Mos) mutation, isolated in the F1 of 60Co-irradiated mosquitoes, confers variegated eye color to third and fourth instar larvae, pupae, and adults of the mosquito Anopheles gambiae. Mos is recessive in wild pink eye (p+) individuals, but is dominant and confers areas of wild-type pigment in mutant pink eye backgrounds. Mos is located 14.4 cM from pink eye on the X chromosome and is associated with a duplication of division 2B euchromatin that has been inserted into division 6 heterochromatin. Various combinations of Mos, pink eye alleles, and the autosomal mutation red eye were produced. In all cases, the darker pigmented regions of the eye in Mos individuals show the phenotypic interactions expected if the phenotype of those regions is due to expression of a p+ allele. Expression of Mos is suppressed by rearing larvae at 32 degrees C relative to 22 degrees C. All of these characteristics are consistent with Mos being a duplicated wild copy of the pink eye gene undergoing position-effect variegation. PMID:10768126