agnosia

Agnosia - loss of the ability of recognition when the safety of the underlying recognition of simple perceptual processes. It arises due to lesions of certain areas of the cerebral cortex of the brain in a tumor , traumatic brain injury and others.

Depending on the location of the lesion there are visual, auditory, tactile and other forms of agnosia. When visual agnosia (lesion of the occipital lobe) patient with intact vision does not recognize the items on their mind can not comprehend or visual picture as a whole, seeing only its individual parts. For partial visual agnosia are alexia (reading disorder due to misrecognition of letters) and color agnosia, in which the patient loses the ability to distinguish colors of objects. When auditory agnosia (loss of the temporal lobe) patients with preserved hearing may not recognize objects by their characteristic sounds (by ticking clock, a dog barking, and so on. N.). Violation of recognition and understanding of speech (voice agnosia, or sensory aphasia) occurs in lesions of the back of the left temporal lobe. When tactile agnosia in patients with preserved sensitivity of simple species violated the ability to recognize objects by their feelings (astereognosis).

Feeling blindly subject the patient describes some of its qualities (size, shape, material from which made the subject), but did not recognize him. Agnosia can manifest itself in misrecognition familiar people, violation of "body schema", due to which the patient does not recognize parts of his own body, feels their increase or decrease. A special type of agnosia is anosognosia, in which the patient is not aware of his illness and denies the existence of associated disorders (paralysis, paresis, etc.); such agnosia typically occurs in patients with lesions of the right hemisphere of the brain.

When agnosia, in addition to treating the underlying disease, you need to participate in the treatment process neuropsychologist to compensate for lost function.