Search results for " blindness"

Analysis of the human a-wave ERG component

2006

The a-wave is one of the main issues of research in the field of ocular electrophysiology, since it is strictly connected with early photoreceptoral activities. The present study proposes mathematical methods that analyse this component in human subjects, and supports experimental evidence relating to possible correlations among the responses of photoreceptoral units under a light stimulus. The investigation is organized in two parts: the first part concerns the onset and the initial slope, up to the first minimum (about 10-15 ms), the second part deals with the main portion of the wave, up to about 30 ms. In both cases, the a-waves, recorded at various levels of luminance, have been fitted…

A Tunable Digital Ishihara Plate for Pre-School Aged Children

2016

Colors play a fundamental role for children, both in the everyday life and in education. They recognize the surrounding world, and play games making a large use of colors. They learn letters and numbers by means of colors. As a consequence, early diagnosis of color blindness is an crucial to support an individual affected by this visual perception alteration at the initial phase of his/her life. The diagnosis of red-green color deficiencies (protanopia or deuteranopia) is commonly accomplished by means of the Ishihara test, which consists of plates showing dots with different sizes where some of them compose numbers within a gamut of colors while the ones composing the background have diffe…

Next-generation sequencing confirms the implication of SLC24A1 in autosomal-recessive congenital stationary night blindness.

2015

Congenital stationary night blindness (CSNB) is a clinically and genetically heterogeneous retinal disorder which represents rod photoreceptor dysfunction or signal transmission defect from photoreceptors to adjacent bipolar cells. Patients displaying photoreceptor dysfunction show a Riggs-electroretinogram (ERG) while patients with a signal transmission defect show a Schubert-Bornschein ERG. The latter group is subdivided into complete or incomplete (ic) CSNB. Only few CSNB cases with Riggs-ERG and only one family with a disease-causing variant in SLC24A1 have been reported. Whole-exome sequencing (WES) in a previously diagnosed icCSNB patient identified a homozygous nonsense variant in SL…

Further delineation of eye manifestations in homozygous 15q13.3 microdeletions including TRPM1: a differential diagnosis of ceroid lipofuscinosis.

2014

The 15q13.3 heterozygous microdeletion is a fairly common microdeletion syndrome with marked clinical variability and incomplete penetrance. The average size of the deletion, which comprises six genes including CHRNA7, is 1.5 Mb. CHRNA7 has been identified as the gene responsible for the neurological phenotype in this microdeletion syndrome. Only seven patients with a homozygous microdeletion that includes at least CHRNA7, and is inherited from both parents have been described in the literature. The aim of this study was to further describe the distinctive eye manifestations from the analysis in the three French patients diagnosed with the classical 1.5 Mb homozygous microdeletion. Patients…

Implicit binding of facial features during change blindness

2014

Change blindness refers to the inability to detect visual changes if introduced together with an eye-movement, blink, flash of light, or with distracting stimuli. Evidence of implicit detection of changed visual features during change blindness has been reported in a number of studies using both behavioral and neurophysiological measurements. However, it is not known whether implicit detection occurs only at the level of single features or whether complex organizations of features can be implicitly detected as well. We tested this in adult humans using intact and scrambled versions of schematic faces as stimuli in a change blindness paradigm while recording event-related potentials (ERPs). …

The temple of visual culture and people with visual impairments: museum accessibility as mental colonization

Accessibility raises political and cultural questions about inclusion and inclusive practices. Museums worldwide now offer multisensory access programs for people with visual impairments, which could appear as an actual implementation of the purpose of the Convention on the Rights of Persons with Disabilities of full inclusion and respect of disabled pleople as part of human diversity. However, by focusing on touch, they often passively exclude people with visual impairments because of their foundation in ocularcentric assumptions about knowledge, misconceptions about visual impairments, and aesthetic and epistemological potential of other 'senses'. Differently, approaches deeply aware of s…

Anger is superior to happiness in change blindness as indicated by behavioral and electrophysiological measures

2012

Therapy Strategies for Usher Syndrome Type 1C in the Retina

2014

The Usher syndrome (USH) is the most common form of inherited deaf-blindness with a prevalence of ~ 1/6,000. Three clinical subtypes (USH1–USH3) are defined according to the severity of the hearing impairment, the presence or absence of vestibular dysfunction and the age of onset of retinitis pigmentosa (RP). USH1 is the most severe subtype with congenital severe to profound hearing loss and onset of RP before puberty. Currently only the amelioration of the hearing deficiency is implemented, but no treatment of the senso-neuronal degeneration in the eye exists.

De Günther Anders al transhumanismo: la obsolescencia del ser humano y la mejora moral

2020

This paper critically compares the philosophy of Gunther Anders and the contemporary transhumanists, like Julian Savulescu, Ingmar Persson, or Thomas Douglas. The Andersian concepts of moral blindness, promethean gap, and promethean shame will be discussed in order to understand human beings’ outdatedness; parallel to this, we will also expose the transhumanist analysis on the unfitness of human beings in evolutive and cognitive terms. We will show that much of the transhumanist analysis is a reformulation of the Andersian thesis, now under scientific terminology. Finally, we will approach the transhumanist proposal of moral enhancement, explaining and confronting some critics raised on the…

A homozygous mutation in the TUB gene associated with retinal dystrophy and obesity.

2013

Inherited retinal dystrophies are a major cause of childhood blindness. Here, we describe the identification of a homozygous frameshift mutation (c.1194_1195delAG, p.Arg398Serfs*9) in TUB in a child from a consanguineous UK Caucasian family investigated using autozygosity mapping and whole-exome sequencing. The proband presented with obesity, night blindness, decreased visual acuity, and electrophysiological features of a rod cone dystrophy. The mutation was also found in two of the proband's siblings with retinal dystrophy and resulted in mislocalization of the truncated protein. In contrast to known forms of retinal dystrophy, including those caused by mutations in the tubby-like protein …