Agnosia

Agnosia - the loss of the ability of recognition in the preservation of the underlying recognition of simple processes of perception. Arises from the lesions of certain areas of the cerebral cortex of the brain in tumors, traumatic brain injury, etc.

Depending on the location of the lesion there are visual, auditory, tactile and other forms of agnosia. With visual agnosia (failure of the occipital lobe) patients with intact vision does not recognize the objects in their mind or can not comprehend the visual picture of the whole, perceiving only its individual parts. By partial visual agnosia are alexia (reading disorder due neuznavaniya 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 can not recognize objects by their characteristic sounds (clock ticking, a dog barking, etc.).

Violation of recognition and understanding of speech (verbal agnosia, or sensory aphasia) occurs in lesions of the posterior parts of the left temporal lobe. When tactile agnosia in a patient with preserved by simple forms of sensitivity is disturbed ability to recognize objects by their feelings (astereognosis).

Feeling with my eyes closed the subject, the patient describes some of its quality (size, shape, material from which made the subject), but did not recognize him. Agnosia may be manifested in neuznavanii familiar people, violating the "body schema", due to which the patient does not know of his own body and feels they increase or decrease. Special type of agnosia is anosognosia, in which the patient is not aware of his illness and denied the existence of related disorders (paralysis, paresis, etc.), such agnosia typically occurs in lesions of the right hemisphere of the brain.

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