Understanding Visual Impairment and Deafblindness

Posted on Jul 7, 2024 in Psychology and Sociology

Visual Impairment

Visual impairment is a permanent alteration in the eyes, on impulse conduction pathways, or the visual cortex, which produces a clear decrease in the ability of vision. Visual impairment ranges from absolute blindness to slight changes in vision. Each situation will have its own needs and will require resources and specific intervention processes.

How to Measure Visual Impairment

An assessment of the level of functioning of the organs of vision, through two parameters:

  1. Visual acuity and visual field:
    • Visual acuity: the image is smaller than the eyes can distinguish. It refers to the fine details of the objects, influences: the actual size of the object, the object’s distance to the eye, and object illumination and contrast of this with the background.
    • The field of view: it refers to the whole portion of space or visual field that the eye can perceive without making moves. Used a test or specific tests and also measured for each eye separately.

Gradations of Visual Impairment

  1. Blindness: insufficient light, disabling for an activity that required the use of vision. Within this is “total blindness”: the complete absence of vision. / / / Part-Blindness: people whose bodies allow them to visual orientation and perception of light mass, but near vision is not enough for school activities and working life. / / / -Hypovision profound: show greater residual vision (20%) than the previous. More defined volumes and colors, near vision facilitates their schooling (reading slower).
  2. Visual weakness: it retains a 30% visual residue allowing schooling, changes in the material. This group can define the concept of low vision or capacity for mass perception, colors and shapes, with limitation for distance. One can distinguish between:
    • Profound visual disability: difficulty with visual tasks thick and inability to perform tasks that require detailed vision.
    • Limitation visual illumination or require a more appropriate presentation of objects, using special glasses or devices.
  3. Amblyopia: is characterized by reduced visual acuity of the retina imperfect sensitivity, without any organic lesion justifying, is known as lazy eye. Can be detected from the 3 or 4 years and 8 or 10 are considered practically irreversible, because the children get the full visual maturity between 9 and 10.

Causes of Blindness

  • Visual hereditary diseases: Color Blindness: total blindness color / / / borne diseases Congenital Rubella: disease that passes from the mother that can cause eye disorders .//// fetal trauma disorders and secondary to other diseases: retinopathy of premature baby: retinal disorders. Excessive oxygen / / / disorders caused by tumors, virus or toxic: Glioma of retina: tumor in the retina.

Functional Limitations of People with Visual Impairment

  • Perception of space occurs through auditory sense, try to capture the sounds that can report changes suffered by the environment.
  • Mobility and daily life skills: with training Rehabilitation Technician Basic and technical aids for the blind can achieve their independence.
  • Social skills: they have difficulties in skills such as postural elements, gaze direction or facial expression, due to lack of imitation
  • Access to written information: aid will need different techniques depending on the degree of deficiency. People with visual waste code will need an extension, however people with little or no waste will need other aids such as Braille and auditory approaches.

Deafblindness

A deafblind person is visually impaired and hearing impaired. This dual sensory loss causes severe learning problems and behaviors in people who suffer, as there is deprivation in the two most important senses. The term deafblindness does not necessarily mean total loss of vision and hearing. Only 10% of deafblind people with such characteristics.

Requirements that People with Deafblindness

Two areas: communication and mobility. The timing of life in which the individual became deafblind has a huge impact on the understanding of their environment and communication, in addition to the daily problems we all face and needs. Those who become blind, deaf in adolescence or adulthood have the benefit of previous exposure to a variety of experiences. The brain receives 95% of everything we know through two senses, such as: hearing and vision. In this way we have the knowledge and give meaning to what is around us. Space give us eyes and ears the world contact us. When these two channels suffer a deterioration in the world this person is restricted to an deafblind person all his feelings, desires, ideas and feelings in the world have the scenario: the hands, body and skin in general, since the meaning of Touch becomes the receiver and sometimes on the issuer of everything in the life of a deafblind person. The sense of the shapes, textures, temperatures of what exists around you is the link that allows these people do not disconnect from the world.

Types of Deafblindness

  1. Those born deafblind or are in a state pre_lingüístico (total or congenital .) Deafblind people left before the acquisition of language. There are likely to imitate their elders, or to explore the environment for themselves (which are the two main sources of learning during the first years of life). / / / /
  2. Deaf congenital lose vision later. Usher Syndrome / / /
  3. Blind birth who lose their hearing. People blind from birth who lose their hearing over time or because of ototoxic drugs. / / /
  4. Those who acquire deafblindness in adult life (post-lingual). Deafblind people left after the acquisition of language.

Usher Syndrome

It is an inherited genetic condition (recessive), which involves hearing loss and progressive loss of vision due to retinitis pigmentosa, which can lead to blindness. Retinitis pigmentosa may occur without hearing loss

Retinitis Pigmentosa Symptoms

  • Night blindness: it is the first symptom. You lose the ability to see well in the dark, to adapt to bright light or rapidly changing light. Usually occurs in adolescence.
  • Narrowing of the visual field: Retinal degeneration is lost ability to locate objects that are in front. The view is like through a tunnel, you lose the perception of the periphery.
  • Acuity loss of central: this is one of the more advanced stages. The eyes lose the ability to see details of things which are against the individual.

Differences Between Deaf and Hearing Loss

  • Deafness: Hearing non-functional for ordinary life, not permitting the acquisition of spoken language through listening. In this case, the vision becomes the main link with the world and the communication channel.
  • Hearing loss: The hearing is poor, but has characteristics such that, with or without prosthesis is functional for ordinary life and allows the acquisition oral language through hearing.