Psychology Facts

▼ Types of Agnosia ▼

The following are specific types of agnosias:

Visual (sight) agnosias

Akinetopsia: This is when you can recognize objects but can't recognize that they're moving.

Alexia: People with this condition can't read. They can still see the words and can write and speak without any problem.

Amusia: The visual effect of this issue causes you to lose the ability to read music (see the auditory effect below).

Autopagnosia: This means you have trouble recognizing body parts, either your own or on another person. You might also have trouble recognizing body parts from a drawing or picture. A sub-type of this is finger agnosia, which means you know what fingers are, but can't recognize them when you see them.

Achromatopsia: Also known as color agnosia, this is where you can see colors and tell them apart, but can't identify the color.

Cortical blindness: This happens when there's damage to the parts of your brain that receive visual input. Your eyes work fine, but your brain can't process the signals sent from your eyes.

Environmental agnosia: This type means you can't recognize where you are, describe a familiar location or give directions to it.

Topographical agnosia is a type of environmental agnosia. Having this means you can remember the specifics of a building layout or its surroundings but can't recognize where you are in relation to the layout and find your way around.

Form agnosia: This is where you can see the parts of an object but can't recognize the object itself. An example of this is identifying the wheels, seat and handlebars of a bicycle when you look at each part, but you can't recognize them as part of the whole bicycle.

Simultagnosia: This is when you have trouble seeing more than one of an object. There are multiple types of this condition.
Dorsal simultanagnosia is where you can only see one object at a time. When you aren't focusing on an object, you can't see it.
Ventral simultanagnosia is where you can see multiple objects at a time, but can only identify them individually. This is like standing in a forest but only recognizing one tree at a time and never recognizing the forest.

Prosopagnosia: Also known as "face-blindness," this condition has two types. Apperceptive prosopagnosia is when you can't recognize a person's facial expressions or other nonverbal cues. Associative prosopagnosia is when you can't recognize a person's face even if you're familiar with them. You can still recognize them by other means, such as their voice or the sound of how they walk. This condition usually happens because of brain damage, but it also has a congenital form, meaning you have it at birth. People born with this have trouble recognizing faces their whole lives. It's possible that congenital prosopagnosia is an inherited condition, as it sometimes runs in families.

Social-emotional agnosia: This is when you can't recognize nonverbal cues like body language. It's similar to apperceptive prosopagnosia (see directly above) but involves a person's whole body rather than just their face.

Auditory (sound) agnosias

Amusia: The auditory effect of this problem means you can't recognize songs or melodies you knew before. You also might not be able to tell music apart from other sounds or recognize specific musical notes.

Auditory agnosia: This is when you can't recognize sounds, even though you have no problem hearing them. When it comes to sounds from people, there are multiple types of this. Verbal auditory agnosia, also known as "word deafness," is when you can't comprehend words spoken aloud. You can still read and write them, and you have no problem speaking words yourself. Nonverbal auditory agnosia is when you can't recognize sounds other people make, but you can understand words they say.

Cortical deafness: Like cortical blindness, this is a problem with certain parts of your brain. Your ears can pick up sounds and send signals to your brain about what they hear. However, damage to certain parts of your brain means your brain can't process those signals.

Phonagnosia: People with this type can't recognize familiar voices, but they have no problem recognizing what a familiar voice is saying.

Tactile (touch) agnosias

Ahylognosia: This is when you can't recognize the properties of an object you touch. That means you can't tell what it's made of, its weight, density or texture. However, you can still recognize it by its shape.

Amorphognosia: This means you can't identify the shape or size of an object by feeling it.
Astereognosis: This is when you can't tell what an object is by feeling it, but you know what the object is by looking at it.

Other agnosias

Anosognosia: This is when you can't recognize that you have a medical condition. This is more than just denial in the sense of not wanting to face the reality of a serious medical condition. This means your brain can't recognize that you have the problem at all. An example of this is having trouble controlling muscle movements from Parkinson's disease but not understanding that you have that condition.

Anosodiaphoria: This is when you recognize that you have a medical condition, but you can't recognize or understand its importance. People with this might downplay a problem because they can't recognize that it's serious.

Gustatory (taste) agnosia: This can affect your ability to recognize types of tastes (sweet vs. bitter) or familiar foods you're tasting.

Olfactory agnosia: This is smell agnosia. Having this means you may not recognize certain smells or types of odors that you previously recognized.

Unilateral neglect: This is a problem where you can't recognize any kind of sensory input on one side of your body. This usually happens because of a lesion on the opposite side of your brain. You also might not recognize the affected side of your body at all.