Conversational Interactions between Mothers and their Infants who are Congenitally Blind, Have Low Vision, or are Sighted

We examined the effect of visual experience on the haptic Müller-Lyer illusion. Subjects made size estimates of raised lines by using a sliding haptic ruler. Independent groups of blindfolded-sighted, late-blind, congenitally blind, and low-vision subjects judged the sizes of wings-in and wings-out stimuli, plain lines, and lines with short vertical ends. An illusion was found, since the wings-in stimuli were judged as shorter than the wings-out patterns and all of the other stimuli. Subjects generally underestimated the lengths of lines. In a second experiment we found a nonsignificant difference between length judgments of raised lines as opposed to smooth wooden dowels. The strength of the haptic illusion depends upon the angles of the wings, with a much stronger illusion for more acute angles. The effect of visual status was nonsignificant, suggesting that spatial distortion in the haptic Müller-Lyer illusion does not depend upon visual imagery or visual experience.

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Perspective Taking: Knowledge of Level 1 and Level 2 Rules by Congenitally Blind, Low Vision, and Sighted Children

Journal of Visual Impairment & Blindness ◽

10.1177/0145482x9508900607 ◽

1995 ◽

Vol 89 (6) ◽

pp. 514-523 ◽

Cited By ~ 4

Author(s):

G. Miletic

Keyword(s):

Perspective Taking ◽

Low Vision ◽

Congenitally Blind ◽

Level 1 ◽

Level 2 ◽

Better Than ◽

Visual Conditions

This article reports on a study of the knowledge of the Level 1 and Level 2 rules of perspective taking by three groups of 8-year-old children with three visual conditions. Although all groups of children had knowledge of the Level 1 rules, their knowledge of the Level 2 rules was affected by their vision. Thus, the sighted children performed better than the children with low vision, and the children with low vision performed better than those who were congenitally blind.

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The Effect of Visual Impairment on the Strength of Children's Hip and Knee Extensors

Journal of Visual Impairment & Blindness ◽

10.1177/0145482x9709100107 ◽

1997 ◽

Vol 91 (1) ◽

pp. 40-46 ◽

Cited By ~ 8

Author(s):

L. Wyatt ◽

G.Y. Ng

Keyword(s):

Body Weight ◽

Visual Impairment ◽

Low Vision ◽

Knee Extensors ◽

Lean Body Weight ◽

Normal Vision ◽

Body Build ◽

Blind Children ◽

Congenitally Blind ◽

Leg Extensors

A test of the strength of children's hip and knee extensors found that children who were congenitally blind or had low vision had weaker knee extensors than did sighted children, but that after the correction for lean body weight (LBW), these differences were not significant. The children who were blind or had low vision also had weaker hip extensors, but after LBW correction, only the blind children's hip extensors were weaker than those of the children with normal vision. The findings indicate that congenitally blind children may be prone to develop weak leg extensors because of poor body build or the constraints of blindness and that they require extensive physical intervention during infancy.

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Tangible Pictures: Viewpoint Effects and Linear Perspective in Visually Impaired People

Perception ◽

10.1068/p3253 ◽

2002 ◽

Vol 31 (6) ◽

pp. 747-769 ◽

Cited By ~ 32

Author(s):

Morton A Heller ◽

Deneen D Brackett ◽

Eric Scroggs ◽

Heather Steffen ◽

Kim Heatherly ◽

...

Keyword(s):

Visually Impaired ◽

Low Vision ◽

Three Dimensional ◽

Linear Perspective ◽

Matching Task ◽

Visually Impaired People ◽

Visual Status ◽

Perspective Drawing ◽

Congenitally Blind ◽

Geometric Solids

Perception of raised-line pictures in blindfolded-sighted, congenitally blind, late-blind, and low-vision subjects was studied in a series of experiments. The major aim of the study was to examine the value of perspective drawings for haptic pictures and visually impaired individuals. In experiment 1, subjects felt two wooden boards joined at 45°, 90°, or 135°, and were instructed to pick the correct perspective drawing from among four choices. The first experiment on perspective found a significant effect of visual status, with much higher performance by the low-vision subjects. Mean performance for the congenitally blind subjects was not significantly different from that of the late-blind and blindfolded-sighted subjects. In a further experiment, blindfolded subjects drew tangible pictures of three-dimensional (3-D) geometric solids, and then engaged in a matching task. Counter to expectations, performance was not impaired for the 3-D drawings as compared with the frontal viewpoints. Subjects were also especially fast and more accurate when matching top views. Experiment 5 showed that top views were easiest for all of the visually impaired subjects, including those who were congenitally blind. Experiment 5 yielded higher performance for 3-D than frontal viewpoints. The results of all of the experiments were consistent with the idea that visual experience is not necessary for understanding perspective drawings of geometrical objects.

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Superior Haptic Perceptual Selectivity in Late-Blind and Very-Low-Vision Subjects

Perception ◽

10.1068/p3423 ◽

2003 ◽

Vol 32 (4) ◽

pp. 499-511 ◽

Cited By ~ 26

Author(s):

Morton A Heller ◽

Kathy Wilson ◽

Heather Steffen ◽

Keiko Yoneyama ◽

Deneen D Brackett

Keyword(s):

Low Vision ◽

Superior Performance ◽

Embedded Figures Test ◽

Embedded Figures ◽

Congenitally Blind ◽

Accuracy Measures

Blindfolded sighted, congenitally blind, late-blind, and very-low-vision subjects were tested on a tangible version of the embedded-figures test. The results of ANOVAs on accuracy measures yielded superior performance by the very-low-vision and late-blind subjects compared with the blindfolded sighted and congenitally blind participants. Accuracy of the congenitally blind subjects was similar to that of the blindfolded sighted participants. However, all groups of blind subjects were significantly faster than the blindfolded sighted subjects. It is suggested that experience with pictures combined with haptic skill aid perceptual selectivity in touch.

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Regions of visual cortex responding to tactile stimulation in an individual with longstanding low vision are not causally involved in tactile processing performance

10.1101/2021.05.18.444648 ◽

2021 ◽

Author(s):

Edward H Silson ◽

Andre D Gouws ◽

Gordon E Legge ◽

Antony B Morland

Keyword(s):

Visual Cortex ◽

Visual Processing ◽

Tactile Stimulation ◽

Low Vision ◽

Repetitive Transcranial Magnetic Stimulation ◽

Somatosensory Cortices ◽

Congenitally Blind ◽

Causal Nature ◽

Blind Individuals ◽

Stimulation Of

Braille reading and other tactile discrimination tasks recruit the visual cortex of both blind and normally sighted individuals undergoing short-term visual deprivation. Prior functional magnetic resonance imaging (fMRI) work in patient S, a visually impaired adult with the rare ability to read both highly magnified print visually and Braille by touch, found that foveal representations of S's visual cortex were recruited during tactile perception, whereas peripheral regions were recruited during visual perception. Here, we test the causal nature of tactile responses in the visual cortex of S by combining tactile and visual psychophysics with repetitive transcranial magnetic stimulation (rTMS). First, we replicate this prior fMRI work in S. Second, we demonstrate that transient disruption of S's foveal visual cortex has no measurable impact on S's tactile processing performance compared to that of healthy controls - a pattern not predicted by the fMRI results. Third, stimulation of foveal visual cortex maximally disrupted visual processing performance in both S and controls, suggesting the possibility of preserved visual function within S's foveal cortex. Finally, stimulation of somatosensory cortex induced the expected disruption to tactile processing performance in both S and controls. These data suggest that tactile responses in S's foveal representation reflect unmasking of latent connections between visual and somatosensory cortices and not behaviourally relevant cross-modal plasticity. Unlike studies in congenitally blind individuals, it is possible that the absence of complete visual loss in S has limited the degree of causally impactful cross-modal reorganisation.

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Temporal changes in conversational interactions induced by the presence of a simultaneous conversation

PsycEXTRA Dataset ◽

10.1037/e512592013-441 ◽

2011 ◽

Author(s):

J. Villegas ◽

V. Aubanel ◽

M. Cooke

Keyword(s):

Temporal Changes ◽

Conversational Interactions

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Komplikasi Pasca Operasi sebagai Faktor Risiko Timbulnya Low Vision Pasca Operasi Katarak

Syifa MEDIKA Jurnal Kedokteran dan Kesehatan ◽

10.32502/sm.v10i1.1689 ◽

2019 ◽

Vol 10 (1) ◽

pp. 11

Author(s):

Rizki Anisa Nurjanah ◽

Septiani Nadra Indawaty ◽

Mitayani Purwoko

Keyword(s):

Low Vision ◽

Cross Sectional

Tajam penglihatan adalah daya lihat yang mampu dilakukan seseorang. Tajam penglihatan normal adalah apabila seseorang dapat melihat huruf, angka, maupun bentuk dalam berbagai macam ukuran pada kartu Snellen dengan jarak 20 kaki (20/20). Katarak merupakan salah satu penyebab terjadinya gangguan penglihatan terbanyak kedua setelah gangguan refraksi yang tidak terkoreksi. Penelitian ini bertujuan untuk mengetahui faktor-faktor yang mempengaruhi timbulnya low vision setelah operasi bedah katarak di Rumah Sakit Muhammadiyah Palembang. Penelitian ini menggunakan desain penelitian deskriptif kuantitatif dengan pendekatan cross sectional menggunakan data rekam medis pasien yang sudah menjalani operasi katarak di Rumah Sakit Muhammadiyah Palembang periode Januari 2017-April 2018. Besar sampel penelitian ini adalah 31 orang. Hasil penelitian ini menunjukkan bahwa pada kontrol keempat pasca operasi, ada 38,7% subjek yang tetap memiliki low vision. Subjek penelitian sebagian besar terdiri dari individu lansia akhir (74,2%), terdapat 2 orang subjek yang mengalami komplikasi intra operasi (6,4%), dan terdapat 9 orang subjek yang mengalami komplikasi pasca operasi (29,1%). Timbulnya lowvision setelah operasi katarak tidak dipengaruhi oleh usia (p = 1,000) dan komplikasi intraoperasi (p = 1,000), namun dipengaruhi oleh adanya komplikasi pasca operasi (p = 0,043). Faktor risiko timbulnya lowvision pasca operasi katarak adalah adanya komplikasi pasca operasi. Oleh karena itu, perlu upaya pencegahan dari berbagai sisi agar tidak terjadi komplikasi pasca operasi katarak.

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