In aphasia, a person may be unable to comprehend or unable to formulate language because of damage to specific brain regions. The major causes are stroke and head trauma; prevalence is hard to determine but aphasia due to stroke is estimated to be 0.1–0.4% in the Global North. Aphasia can also be the result of brain tumors, epilepsy, autoimmune neurological diseases, brain infections, or neurodegenerative diseases.
Expressive aphasia, also known as Broca's aphasia, is a type of aphasia characterized by partial loss of the ability to produce language, although comprehension generally remains intact. A person with expressive aphasia will exhibit effortful speech. Speech generally includes important content words but leaves out function words that have more grammatical significance than physical meaning, such as prepositions and articles. This is known as "telegraphic speech". The person's intended message may still be understood, but their sentence will not be grammatically correct. In very severe forms of expressive aphasia, a person may only speak using single word utterances. Typically, comprehension is mildly to moderately impaired in expressive aphasia due to difficulty understanding complex grammar.
Wernicke's aphasia, also known as receptive aphasia, sensory aphasia or posterior aphasia, is a type of aphasia in which individuals have difficulty understanding written and spoken language. Patients with Wernicke's aphasia demonstrate fluent speech, which is characterized by typical speech rate, intact syntactic abilities and effortless speech output. Writing often reflects speech in that it tends to lack content or meaning. In most cases, motor deficits do not occur in individuals with Wernicke's aphasia. Therefore, they may produce a large amount of speech without much meaning. Individuals with Wernicke's aphasia are typically unaware of their errors in speech and do not realize their speech may lack meaning. They typically remain unaware of even their most profound language deficits.
Anomic aphasia is a mild, fluent type of aphasia where individuals have word retrieval failures and cannot express the words they want to say. By contrast, anomia is a deficit of expressive language, and a symptom of all forms of aphasia, but patients whose primary deficit is word retrieval are diagnosed with anomic aphasia. Individuals with aphasia who display anomia can often describe an object in detail and maybe even use hand gestures to demonstrate how the object is used, but cannot find the appropriate word to name the object. Patients with anomic aphasia have relatively preserved speech fluency, repetition, comprehension, and grammatical speech.
Conduction aphasia, also called associative aphasia, is an uncommon form of difficulty in speaking (aphasia). It is caused by damage to the parietal lobe of the brain. An acquired language disorder, it is characterised by intact auditory comprehension, coherent speech production, but poor speech repetition. Affected people are fully capable of understanding what they are hearing, but fail to encode phonological information for production. This deficit is load-sensitive as the person shows significant difficulty repeating phrases, particularly as the phrases increase in length and complexity and as they stumble over words they are attempting to pronounce. People have frequent errors during spontaneous speech, such as substituting or transposing sounds. They are also aware of their errors and will show significant difficulty correcting them.
Global aphasia is a severe form of nonfluent aphasia, caused by damage to the left side of the brain, that affects receptive and expressive language skills as well as auditory and visual comprehension. Acquired impairments of communicative abilities are present across all language modalities, impacting language production, comprehension, and repetition. Patients with global aphasia may be able to verbalize a few short utterances and use non-word neologisms, but their overall production ability is limited. Their ability to repeat words, utterances, or phrases is also affected. Due to the preservation of the right hemisphere, an individual with global aphasia may still be able to express themselves through facial expressions, gestures, and intonation. This type of aphasia often results from a large lesion of the left perisylvian cortex. The lesion is caused by an occlusion of the left middle cerebral artery and is associated with damage to Broca's area, Wernicke's area, and insular regions which are associated with aspects of language.
Transcortical sensory aphasia (TSA) is a kind of aphasia that involves damage to specific areas of the temporal lobe of the brain, resulting in symptoms such as poor auditory comprehension, relatively intact repetition, and fluent speech with semantic paraphasias present. TSA is a fluent aphasia similar to Wernicke's aphasia, with the exception of a strong ability to repeat words and phrases. The person may repeat questions rather than answer them ("echolalia").
DIBELS is a series of short tests designed to evaluate key literacy skills among students in kindergarten through 8th grade, such as phonemic awareness, alphabetic principle, accuracy, fluency, and comprehension. The theory behind DIBELS is that giving students a number of quick tests, will allow educators to identify students who need additional assistance and later monitor the effectiveness of intervention strategies.
Mixed transcortical aphasia is the least common of the three transcortical aphasias. This type of aphasia can also be referred to as "Isolation Aphasia". This type of aphasia is a result of damage that isolates the language areas from other brain regions. Broca's, Wernicke's, and the arcuate fasiculus are left intact; however, they are isolated from other brain regions.
The Wechsler Intelligence Scale for Children (WISC) is an individually administered intelligence test for children between the ages of 6 and 16. The Fifth Edition is the most recent version.
Alan S. Kaufman is an American psychologist, writer, and research professor known for his work on intelligence testing.
The Boston Diagnostic Aphasia Examination is a neuropsychological battery used to evaluate adults suspected of having aphasia, and is currently in its third edition. It was created by Harold Goodglass and Edith Kaplan. The exam evaluates language skills based on perceptual modalities, processing functions, and response modalities. Administration time ranges from 20 to 45 minutes for the shortened version but it can last up to 120 minutes for the extended version of the assessment. There are five subtests which include: conversational & expository speech, auditory comprehension, oral expression, reading, and writing. In the extended version all questions are asked while in the shortened version only a few questions are asked within each subtest. Many other tests are sometimes used by neurologists and speech language pathologists on a case-by-case basis, and other comprehensive tests exist like the Western Aphasia Battery.
Aprosodia is a neurological condition characterized by the inability of a person to properly convey or interpret emotional prosody. Prosody in language refers to the ranges of rhythm, pitch, stress, intonation, etc. These neurological deficits can be the result of damage of some form to the non-dominant hemisphere areas of language production. The prevalence of aprosodias in individuals is currently unknown, as testing for aprosodia secondary to other brain injury is only a recent occurrence.
The comprehensive aphasia test (CAT) was created by Kate Swinburn, Gillian Porter and David Howard. The CAT is a new test for people who have acquired aphasia, the impairment of language ability. The comprehensive assessment can be completed over one or two sessions. The test contains a cognitive screening, a language battery and a disability questionnaire. The authors of the comprehensive aphasia test take account of current linguistic and psychological theory and other variable that impact aphasic performance. The CAT was published in 2005 and was the first new aphasia test in English for 20 years. The test is designed to (1) screen for associated cognitive deficits,(2) assess language impairment in people with aphasia, (3) investigate the consequences of the aphasia on the individual's lifestyle and emotional well-being, and (4) monitor changes in the aphasia and its consequences over time.
The Wechsler Individual Achievement Test Second Edition assesses the academic achievement of children, adolescents, college students and adults, aged 4 through 85. The test enables the assessment of a broad range of academics skills or only a particular area of need. The WIAT-II is a revision of the original WIAT, and additional measures. There are four basic scales: Reading, Math, Writing and Oral Language. Within these scales there is a total of 9 sub-test scores.
The Peabody Individual Achievement Test is a criterion based survey of an individual’s scholastic attainment. It can be administered to individuals between the ages of five and 22 years of age, and returns a grade range between Kindergarten and grade 12. The test is available in English and Spanish.
Empathy quotient (EQ) is a psychological self-report measure of empathy developed by Simon Baron-Cohen and Sally Wheelwright at the Autism Research Centre at the University of Cambridge. EQ is based on a definition of empathy that includes cognition and affect.
Verbal intelligence is the ability to understand and reason using concepts framed in words. More broadly, it is linked to problem solving, abstract reasoning, and working memory. Verbal intelligence is one of the most g-loaded abilities.
Language and Language Disturbances: Aphasic Symptom Complexes and Their Significance for Medicine and Theory of Language is a book on aphasia by Dr. Kurt Goldstein, published in 1948. In Language and Language Disturbances, Goldstein theorized that a loss of abstract processing was the core deficit in aphasia.
The Attribution Questionnaire (AQ) is a 27-item self-report assessment tool designed to measure public stigma towards people with mental illnesses. It assesses emotional reaction and discriminatory responses based on answers to a hypothetical vignette about a man with schizophrenia named Harry. There are several different versions of the vignette that test multiple forms of attribution. Responses assessing stigma towards Harry are in the form of 27 items rated on a Likert scale ranging from 1 (not at all) to 9 (very much). There are 9 subscales within the AQ that breakdown the responses one could have towards a person with mental illness into different categories. The AQ was created in 2003 by Dr. Patrick Corrigan and colleagues and has since been revised into smaller tests because of the complexity and hypothetical that did not capture children and adolescent's stigmas well. The later scales are the Attribution Questionnaire-9 (AQ-9), the revised Attribution Questionnaire (r-AQ), and the children's Attribution Questionnaire (AQ-8-C).
