What is Aphasia, its Types, Diagnosis, and Treatment

The brain has many different areas responsible for controlling daily behaviors. Among these areas are those that help with understanding, speaking, and maintaining communication. Trauma occurring in specific regions responsible for these tasks can result in acquired dysfunction, leading to difficulties in understanding and speaking. This anomaly, often resulting from an illness, is called aphasia. Aphasia can vary depending on the person's ability to perceive the tools used for speaking, understanding, and communication. In the most common types of aphasia, patients may not be able to understand what is being said or may give meaningless responses to what they hear. Aphasia is one of those conditions that, with accurate diagnosis, treatment, and a positive effect from both the patient and their caregivers on the recovery process, can be reversible.

What is Aphasia?

There are areas in the brain responsible for understanding spoken words and producing meaningful speech. These areas in the cortex are essential for communication and enable the person to maintain their language functions through different means. These regions are usually found in the left hemisphere of the brain. Damage to these areas in the left hemisphere leads to impairments in the person’s speaking ability. The most common types of aphasia are those resulting from trauma, such as a stroke, which causes partial disruption of blood flow to the brain. Aphasia patients are typically middle-aged or elderly. All aphasia patients, depending on the severity of the disease, share common problems. These patients may either fail to understand spoken words and attempt to respond with meaningless words, or they may understand the words but struggle to form sentences. Different types of aphasia are classified based on the severity of the disease and the person's ability to use and understand language.

What are the Causes of Aphasia?

There are various underlying diseases that can cause aphasia. It is generally known that aphasia develops due to trauma. In addition, aphasia can also occur in diseases with a high hereditary development rate, such as dementia. In progressive aphasia, which develops over time, issues such as slow speech, forgetting words, being unable to produce words, speaking in pauses, and inability to understand what is said are similar to those seen in trauma-induced aphasia. In aphasia caused by trauma, there is a disruption of nutrition in the brain, and the areas responsible for language production lose their function. The brain is an organ that consumes oxygen every second and uses glucose as its primary fuel. If oxygen deprivation lasts for several minutes, it creates a nutritional problem in the brain. The primary cause of brain nutritional disorders leading to aphasia is stroke, commonly known as a brain attack. Infections, trauma, head injuries, and tumors that occur in the brain can also cause aphasia by blocking blood flow in a similar way.

Two important areas in the cortex, the main functional part of the brain, are damaged in trauma. These areas responsible for understanding and comprehending speech are known as Wernicke's area and Broca's area. Wernicke's area is located in the temporal lobe, just above the left ear, while Broca's area is located in the frontal lobe, in the left temple. Wernicke's area is responsible for understanding spoken and written language, while Broca's area is responsible for expressing language and speaking. Damage to either of these areas leads to difficulties in understanding and speaking.

What are the Symptoms of Aphasia?

Depending on the type of aphasia, there may be different symptoms that can affect diagnosis. However, patients suspected of having aphasia usually show common symptoms. All of these symptoms manifest as difficulties in language production, understanding spoken and written language, and issues related to speaking. The most common symptoms displayed by patients suspected of aphasia when visiting clinics are:

• Speaking in pauses
• Inability to understand what is said
• Inability to repeat what is said to them
• Difficulty forming meaningful sentences by combining meaningful words
• Struggling to generate words before speaking
• Inability to understand or read written words
• Using grammatically incorrect expressions

In patients showing these symptoms, the common issue is difficulty speaking and understanding in the language they previously spoke. The combination of these symptoms can vary depending on the type of aphasia.

What are the Types of Aphasia?

Aphasia can vary depending on cortical damage. The brain damage and the symptoms of the disease can differ based on the type of aphasia. The Wernicke and Broca areas in the left hemisphere of the brain are the most important points responsible for aphasia. Particularly, damage to either or both of these areas significantly influences the severity of the disease. Aphasia types are classified according to their symptoms and findings as follows:

• Wernicke's Aphasia (Fluent Aphasia): Wernicke’s area is responsible for understanding speech and written text. A patient with damage to this area can listen to what is spoken but cannot form sentences related to the content when it is their turn to speak. The person can speak and write, but what they say and express is completely meaningless. Although they may form grammatically correct sentences, they cannot give the desired responses. For example, in response to the question “Would you like a glass of water?” they might say something unrelated, such as “I will return by bus tomorrow.”
• Broca's Aphasia (Non-Fluent Aphasia): The person listens to and understands the other party in a conversation, but cannot provide meaningful responses. In this type of aphasia, the patient experiences pauses while constructing sentences, difficulty remembering words, and the creation of grammatically incorrect sentences. When attempting to speak, the patient moves their mouth and tongue, but struggles to produce words, showing signs of hesitation.
• Global Aphasia: This is the most severe form of aphasia. It involves dysfunction in both the Wernicke and Broca areas. Patients with global aphasia cannot understand spoken or written language, nor can they respond to what is said or read. These patients typically attempt to communicate using meaningless sounds and facial expressions.
• Progressive Aphasia: This aphasia develops secondarily due to an underlying disease. It is a progressive type of aphasia caused by conditions such as dementia, migraines, frontotemporal lobar damage, and atrophy in the frontal and temporal lobes.
• Transcortical Aphasia: This type of aphasia exhibits similar symptoms to Wernicke’s aphasia. The patient may speak fluently and form meaningful sentences, although these sentences may not relate to the context. However, they retain the ability to repeat what is said to them.
• Conduction Aphasia (Transmission Aphasia): In these patients, the areas responsible for language production and comprehension remain intact, but the nerve networks connecting these two areas are damaged. People with conduction aphasia can speak, understand spoken language, write, and read. However, speech and writing may sometimes show slight changes in sound, although these changes are not as severe as those seen in Broca’s aphasia.
• Anomic Aphasia: The main issue in patients with anomic aphasia is the inability to recall the names of objects and associate the object with its corresponding word. When referring to objects in a sentence, they often use vague terms like "thing," "this," or "that" instead of naming the object.

How is Aphasia Diagnosed?

Aphasia is diagnosed by a specialist neurologist based on communication and comprehension issues in the individual. The diagnosis involves various parameters, including the patient's medical history, family genetics, diagnostic imaging methods, speech tests, grammar and expression tests. The definitive diagnosis is made through imaging methods conducted while the patient is speaking and listening to what is being said.

Aphasia Treatment

If there is a pathophysiological condition causing the disease, the primary goal is to correct it surgically. However, in cases of aphasia caused by stroke, infection, or trauma, therapy is the first option. Treatments such as memory-enhancing tests, speech therapies, increasing verbal cues and repetitions, and practicing communication with the environment are recommended for these patients. Once a neurologist diagnoses aphasia, recovery is possible through collaborative treatment with speech and language therapists in a multidisciplinary approach. Although the development and recovery process may differ for each patient, significant improvements in the treatment of the disease can be observed.

For examination, diagnosis, and treatment of aphasia and other neurodegenerative diseases, you can call and schedule an appointment with our specialist doctors to receive support from experienced physicians during the recovery process.