To diagnose aphasia, doctors first carefully assess the patient's symptoms and language skills. This clinical examination is a critical step in determining the type and severity of aphasia. Further diagnostic tests are then utilized to confirm the diagnosis, identify the underlying cause of aphasia (such as stroke, tumor, or traumatic brain injury), and visualize the affected areas of the brain.

The most commonly used imaging tests in the diagnosis of aphasia include:

* Computed Tomography (CT) scan
* Magnetic Resonance Imaging (MRI)