Aphasia is a communication disorder that occurs as a result of damage to the brain that affects the language dominant hemisphere and causes problems in the individual’s understanding, production and use of language (Lapointe, 2004; Papathanasiou et al., 2012). As a result of aphasia, in all components of language (syntax, semantic, morphological, pragmatic) and in all language modalities (speaking, writing, reading, singing); both receptive and expressive problems may arise (Papathanasiou et al., 2012). Aphasia is a condition that disrupts the daily life of the individual by affecting the intonation, time awareness, mathematical operations and simple operations such as traffic signs, warning sirens of vehicles, money account, as well as reading, writing, speaking and using gestures (Lapointe, 2004). It occurs as a result of dysfunction in the central nervous system and is a multifaceted disorder (Lapointe, 2004). It affects not only the language areas of the individual’s brain, but also the nervous system, which includes thinking, memory, controlling information processing and other cognitive functions (Lapointe, 2004). However, it is still very difficult to classify. Because cognitive problems occur in acquired language disorders (Wiig, Alexander, & Secord, 1988, Papathanasiou et al., 2012).
Etiology of Aphasia
A cerebrovascular accident or stroke causes aphasia. A stroke or brain attack occurs when blood flow to the brain is absent or reduced. Thanks to this transported blood flow, the brain receives the nutrients it needs. If the brain cells do not receive these nutrients over a certain period of time, death or damage begins to occur in the brain cells. Blood clot, traumatic brain injury, tumors in the brain, abnormal cell growth can cause aphasia. Alzheimer’s, Parkinson’s and other neurodegenerative diseases can cause brain damage, resulting in impairments in memory, problem solving, judgment, organization and planning, and language functions. (Lapointe, 2004)
In addition to determining the lesion sites in the classification of aphasia; Evaluation of components of language, analysis of speech, repetition, auditory comprehension, reading and writing are evaluated.
Broca’s Aphasia: It is the loss of almost all components of the language (Ardila, 2010). Individuals with Broca’s aphasia have very limited or no grammar, they can only say and understand words in isolation. They may not remember spatial concepts in the language. They can replace the used suffixes with other suffixes or they may not use the suffixes at all (Ardila, 2010; Caplan, 2006; Ozeren, 2002). The most common conditions in Broca’s aphasia are;
1. Articulation disorders are seen due to problems in the motor component of speech (Ardila, 2010).
2. Agramatism. In some cases, they can say sentences by reducing them to a single word level (Caplan, 2006).
Individuals with Broca’s aphasia may be considered to have no comprehension disorder during simple speech; however, a complex speech reveals that these individuals have comprehension difficulties (Özeren, 2002).
Wernice’s Aphasia; It is a situation where the lexical repertoire decreases and there are difficulties in understanding the language (Ardila, 2010). Individuals with Wernice aphasia cannot fully distinguish the acoustic signals in speech, have difficulty in lexical and semantic relationships, and phoneme and word choices are affected. However, the syntax has been largely preserved (Ardila, 2010). These individuals have difficulty in calling words and associating the word with its meaning. Therefore, individuals with Wernice aphasia experience difficulties in 3 areas.
1. Phoneme discrimination (auditory-verbal agnosia),
2. Verbal memory,
3. Lexical/semantic association (Ardila, 1993).
Transcotical Sensory Aphasia; It is a type of aphasia characterized by fluent speech, impaired comprehension, and preservation of repetition. The most important feature that distinguishes this type of aphasia from Wernice’s aphasia is the presence of recurrence (Özeren, 2002). While speaking, they can often speak out of context (Ardila, 2010).
Transcortical Motor Aphasia; It is a situation where repetition is preserved but there is no fluent speech, phonemic and global paraphasia, and no naming (Schoeman & Merwe, 2010¸ Özeren, 2002; Ardila, 2010).
anomie; Speech is fluent, articulation and grammatical errors are absent during speaking; however, it is a situation where naming difficulties are experienced.
Conduction Aphasia; It is a type of aphasia in which spontaneous speech is close to normal and fluent, grammatically correct, but there are paraphasias and naming difficulties are experienced (Özeren, 2002).
Global Aphasia; It is a condition in which verbal communication skills are almost completely affected, there is a fluent speech, and all components of auditory comprehension and language are affected (Schoeman & Merwe, 2010).