What is what: typologies
The foremost requirement for the process of vision is a fundamental element: light, a form of electromagnetic energy. This light enters our eyes and interacts with the photosensitive receptors positioned on the retina. This interaction initiates a sequence of events in which neural impulses are generated. These impulses traverse intricate pathways and networks within the brain dedicated to vision, collectively referred to as the visual cortex. The incoming light is further directed onto the retina’s rear surface through the lens, which is known as the crystalline lens. The retina’s receptors detect this luminous energy and, via a process termed transduction, convert it into action potentials. These potentials subsequently travel along the optic nerve.
In the realm of visual health, Dr. Ananya Mandal, MD, defines visual impairment as a “functional limitation affecting the eye or eyes, or the entire visual system.” This impairment leads to a range of effects, including:
Diminished visual acuity, causing a person to perceive objects less sharply than someone with a normal
Reduced visual field, wherein an individual cannot observe as broad an expanse as an average person without shifting their gaze or turning their head.
Photophobia, an inability to tolerate or gaze at
Diplopia, commonly referred to as double
Visual distortion, involving the deformation of
Challenges in visual perception or the act of interpreting visual
Combinations of the features.
As per the pronouncements of the World Health Organization (WHO), an individual is categorized as severely sight impaired, or blind, when the visual acuity in their best eye used for perceiving details remains below 1/20, even with the most effective correction. On the other hand, an individual is classified as sight impaired, or partially sighted, if their visual acuity falls between 3/10 and 1/20. However, this classification system originates from two decades ago. More recently, the International Statistical Classification of Diseases and Related Health Problems 10th Revision (ICD-10) – WHO Version for 2016 has introduced a new classification scheme. This updated scheme outlines five distinct categories within Chapter VII: Diseases of the eye and adnexa (H00-H59), specifically focusing on Visual disturbances and blindness (H53-H54).
H53Visual disturbances
H53.0 – Amblyopia ex anopsia
Amblyopia:
Anisometropic
Deprivation
Strabismic
H53.1 – Subjective visual disturbances
Asthenopia Day blindness Hemeralopia
Metamorphopsia Photophobia Scintillating scotoma Sudden visual loss Visual halos
Excl.: visual hallucinations
H53.2 – Diplopia
Double vision
H53.3 – Other disorders of binocular vision
Abnormal retinal correspondence Fusion with defective stereopsis
Simultaneous visual perception without fusion Suppression of binocular vision
H53.4 – Visual field defects
Enlarged blind spot
Generalized contraction of visual field Hemianop(s)ia (heteronymous)(homonymous) Quadrant anop(s)ia
Scotoma:
Arcuate
Bjerrum
Central
Ring
H53.5 – Colour vision deficiencies
Achromatopsia
Acquired colour vision deficiency Colour blindness
Deuteranomaly
Deuteranopia Protanomaly Protanopia Tritanomaly Tritanopia
Excl.: Day blindness
H53.6 – Night blindness
Excl.: Due to vitamin A deficiency
H53.8 – Other visual disturbances
H53.9 – Visual disturbance, unspecified
H54Visual impairment including blindness (binocular or monocular)
Note: For definition of visual impairment categories see table below.
Excl.: Amaurosis fugax
H54.0 – Blindness, binocular
Visual impairment categories 3,4,5 in both eyes
H54.1 – Severe visual impairment, binocular
Visual impairment category 2.
H54.2 – Moderate visual impairment, binocular
Visual impairment category 1
H54.3 – Mild or no visual impairment, binocular
Visual impairment category 0.
H54.4 – Blindness, monocular
Visual impairment categories 3, 4, 5 in one eye and categories 0, 1, 2 or 9 in the other eye.
H54.5 – Severe visual impairment, monocular
Visual impairment category 2 in one eye and categories 0, 1 or 9 in other eye.
H54.6 – Moderate visual impairment, monocular
Visual impairment category 1 in one eye and categories 0 or 9 in other eye.
H54.9 – Unspecified visual impairment (binocular)
Visual impairment category 9.
As depicted on the WHO website, the provided table presents a categorization of the severity of visual impairment that has been endorsed by the International Council of Ophthalmology’s Resolution and the guidelines put forth by the WHO Consultation on “Development of Standards for Characterization of Vision Loss and Visual Functioning”.
Figure 1: categorization of the severity of the visual impairment (Source: (ICD-10 Version:2016, n.d.))
“Note: The term visual impairment in category H54 comprises category 0 for mild or no visual impairment, category 1 for moderate visual impairment, category 2 for severe visual impairment, categories 3, 4 and 5 for blindness and category 9 for unqualified visual impairment. The term “low vision” included in the previous revision has been replaced by categories 1 and 2 to avoid confusion with those requiring low vision care.” (ICD- 10 Version:2016, n.d.)
Visual impairment represents the big umbrella to cover all previous categories (blindness and partial sight) in H54. However, the intricacies of each case are distinct. Only a minority among those registered as blind or partially sighted lack any form of vision, while varying eye conditions react diversely to factors like shifts in lighting. Some individuals might have the ability to read but require assistance for safe mobility. Whatever the condition, the best approach to ascertaining a person’s visual ability is to ask them when they are alone and discuss with them how they would prefer to be supported” (VISION, n.d.)
Virtual examples
Before we proceed with providing instructions and guidelines for engaging with visually impaired (V.I) students both within the education system and in ceramics workshops, it seems appropriate to offer sighted users of this training program an insight (through examples) into the potential visual experiences of individuals with various types of visual impairments.
The following slides, crafted by the SIGMA team, illustrate how individuals with specific eye conditions might perceive a given situation differently compared to those with full sight. It’s important to acknowledge that we can’t precisely comprehend the visual experiences of others, and these slides serve as an approximation. As noted above, the way people understand an object is influenced not solely by their visual input, but also by how their brain processes and interprets visual information.
Here below, a general introduction to the different types of vision:
Figure 2: Subsequent eye diseases by slide group (condition) (source: (VISION, n.d.)
Based on these different types of visions and visual impairments, what are the main barriers they encounter when being part of a group and interacting with others?
What are the main barriers they usually encounter when moving into new spaces and during their experiential learning (thus using the 5 senses) within ceramic workshops?
Barriers when experiencing team building within ceramic workshops.
For V.I youngsters, the difficulties in this situation can encompass:
Identify your team and their positions, but also understand other feelings because of the impossibility to recognize facial expressions and body movements/gestures etc. So, there is a big problem linked to social interactions.
Move in the room, while avoiding obstacles and physical barriers, but also security linked to the use of dangerous
Staying informed about changes in team members, such as someone leaving or joining.
Knowing when to take your turn in the discussion or
Requiring additional time to access visual materials, such as cards on presentation slides. Need to ensure the accessibility of all materials, in accessible formats (electronic text or brail) avoiding standard printed
Requiring assistive technology, for instance the use of screen readers and braille displays. In general, tactile and multi-sensory experience are strongly recommended. These processes enable the blind and visually impaired to construct and elaborate personalized patterns and structures for memorizing information in an easier way.
| Tunnel vision – loss of peripheral vision
|
Peripheral vision – no central vision
|
Patchy vision – missing areas
|
| Blurred vision – Nystagmus
|
Reduced visual acuity – poor contrast
|
Reduced vision – too much light
|
Barriers linked on how to manage space and recognise objects within a ceramic workshop
For the V.I youngsters, the difficulties here may include:
- Object detection and recognition. To overcome this problem, blind people often just use their memory and labeling systems to help them locate and recognize objects in space.
- Recognize objects that are similar in shape or recognize linear patterns of objects.
- Perception of correct shapes of objects.
Pay attention:
- For a visually impaired person, knowledge of a space and the objects in it presupposes a mental representation that is built through a long and laborious process of collecting and reworking data (thus using memory and mental faculties) and it will be acquired mainly through tactile exploration.
- For a visually impaired person, the location of the objects is very important. Ensure that the objects in the classrooms are always located in the same place, so that the V.I students don’t have to continually change the acquired references (in terms of where the object is located), reorganize the information they obtained before and change their spatial map of reference.
Tunnel vision – loss of peripheral vision  |
Peripheral vision – no central vision
|
Patchy vision – missing areas
|
| Blurred vision – Nystagmus
|
Reduced visual acuity – poor contrast
|
Reduced vision –too much light
|
Sum-up matrix for teachers on how to behave correctly in order to meet the needs of their V.I youngsters.
Introduce the learning environments and the people in it!
Introduce yourself as a a teacher.
Explain your role in providing individual support and emotional assistance if needed (ask the visually impaired person if he/she needs your help).
Explain the learning environment to your V.I students (where the objects are located, how the team is composed by possible physical barriers and how to avoid dangers when moving into a new space).
Ensure that everyone is correctly informed about possible risks and security measures to be faced!
Let them touch you if they need your guidance.
Be ½ step in front of them, so that they can follow you easily.
When walking with visually impaired individuals, talk to them comfortably and inform them about the buildings and the marks.
To describe your path, use words, like front-back, left, or right.
When you are stepping away, you should announce it.
Ensure emotional support and promote positive relationships within the group!
Ask them directly without hesitation about their preferences and their hobbies or whatever you want to ask them considering their disabilities.
Explore their feelings in order to be able to understand possible conflicts or bad feelings that can occur during the workshops.
Talk to them in a natural tone of voice, avoiding stress and Try to adopt positive behavioral and motivational speech.