Visual agnosia is a neurological disorder that affects a person's ability to recognize or interpret visual stimuli, despite having intact visual function. This disorder can manifest itself in different forms, each with its own distinctive characteristics and symptoms. In this article, we will explore the 6 main types of visual agnosia and their associated symptoms.
1. Associative visual agnosia
Associative visual agnosia is a type of disorder in which the affected person has difficulty recognizing familiar objects, faces, or visual stimuli, despite being able to perceive them clearly. In this case, the alteration is found in the ability to associate the visual stimulus with its meaning or name.
Symptoms:
- Difficulty recognizing common objects, such as a cup or a telephone.
- Inability to identify familiar faces, such as those of family or friends.
- Problems assigning names to familiar objects or images.
2. Integrative visual agnosia
In integrative visual agnosia, the person has difficulty understanding the arrangement or structure of a set of visual elements, which makes it difficult to overall perceive the visual scene. Despite being able to recognize objects individually, the person cannot integrate them into a coherent whole.
Symptoms:
- Difficulty identifying the shape of an object when it is partially hidden .
- Inability to recognize a complete visual pattern or design.
- Problems understanding the spatial relationship between elements of a visual scene.
3. Visual agnosia simultagnosia
Visual agnosia simultagnosia is characterized by the inability to perceive more than one object at a time in a complex visual scene. The affected person can only process one visual element at a time, making it difficult to comprehensively understand a complex visual situation.
Symptoms:
- Difficulty identifying several objects present in a visual scene simultaneously.
- Inability to perform tasks that require the perception of multiple visual elements at the same time.
- Problems following a moving object within a dynamic visual scene.
4. Visual agnosia for moving objects
In visual agnosia for moving objects, the affected person has difficulty perceiving and processing moving objects. Although you can clearly see stationary objects, you experience problems correctly interpreting the speed, direction, and trajectory of moving objects.
Symptoms:
- Difficulty estimating the speed of a moving object.
- Inability to predict the trajectory of a moving object.
- Problems visually tracking a rapidly moving object.
5. Visual agnosia for faces (prosopagnosia)
Prosopagnosia, also known as visual agnosia for faces, is a specific disorder in which the affected person has difficulty recognizing or remembering familiar faces. Although you can clearly see facial details, you find it impossible to associate them with the corresponding identity.
Symptoms:
- Inability to recognize faces of family members, friends or well-known public figures.
- Difficulty remembering what a person's face looks like even after having seen them several times.
- Problems identifying emotions or facial expressions in the faces of others.
- /ul>
6. Visual agnosia for colors (achromatopsia)
Achromatopsia is a type of visual agnosia in which the affected person experiences an alteration in the perception of colors. In this case, the person can see objects and scenes in black and white or in shades of gray, which affects their ability to recognize and distinguish colors correctly.
Symptoms:
- Seeing in black and white or shades of gray instead of bright colors.
- Difficulty identifying specific colors, especially in similar objects but different shades.
- Inability to appreciate the chromatic richness of a visual scene.
In conclusion, visual agnosia encompasses a variety of disorders that affect a person's ability to recognize, interpret and process visual stimuli. Each type of visual agnosia presents specific symptoms that require precise evaluation and diagnosis for proper management. If you suspect that you or someone you know may be experiencing any of these symptoms, it is important to seek advice from a health professional specialized in neurology and visual disorders.