However, imaging cannot diagnose anomia on its own because the lesions may not be located deep enough to damage the white matter or the arcuate fasciculus. However, anomic aphasia is very difficult to associate with a specific lesion location in the brain. Therefore, the combination of speech tests and imaging tests has the highest sensitivity and specificity.Picture-naming tests, such as the Philadelphia Naming Test (PNT), are also utilized in diagnosing aphasias. Analysis of picture-naming is compared with reading, picture categorizing, and word categorizing. There is a considerable similarity among aphasia syndromes in terms of picture-naming behavior, however anomic aphasiacs produced the fewest phonemic errors and the most multiword circumlocutions. These results suggest minimal word-production difficulty in anomic aphasia relative to other aphasia syndromes.Anomic aphasia has been diagnosed in some studies using the Aachen Aphasia Test (AAT), which tests language functioning after brain injury. This test aims to: identify the presence of aphasia; provide a profile of the speakers language functioning according to different language modalities (speaking, listening, reading, writing) and different levels of linguistic description (phonology, morphology, semantics, and syntax); give a measure of severity of any breakdown. This test was administered to patients participating in a study in 2012, and researchers found that on the naming subtest of the AAT patients showed relevant naming difficulties and tended to substitute the words they could not produce with circumlocutions.The Western Aphasia Battery is another test that is conducted with the goal of classifying aphasia subtypes and rating the severity of the aphasiac impairment.
Thus, this somatosensory information would fail to be transmitted to language areas in the left hemisphere, in turn resulting in the inability to name the object in the left hand. In this example, the patient would have no problem with naming, if the test object were to be held in the right hand. This type of anomia may also arise as a consequence of a disconnect between sensory and language cortices. Articulatory initiation anomia results from damage to the frontal area. Characteristics of this anomia are non-fluent output, word-finding pauses, deficient word lists. Patients perform better at confrontation naming tasks, the selection of a label for a corresponding picture, than word list tasks. Patients are aided in word selection by prompting, unlike those with word selection anomia. Phonemic substitution anomia results from damage to the inferior parietal area. Patients maintain fluent output but exhibit literal and neologistic paraphasia. Literal paraphasia is the incorrect substitution of phonemes, and neologistic paraphasia is the use of non-real words in the place of real words. Patients naming ability is contaminated by paraphasia. Modality-specific anomia is caused by damage to the sensory cortex, pathways to the dominant angular gyrus, or both. In these patients, word-finding is worst in one sensory modality, for example visual or tactile. Causes
Anomic aphasia occurring by itself may be caused by damage to almost anywhere in the left hemisphere and in some cases can be seen in instances of right hemisphere damage.