Neurological Loss of Language Skills
October 5, 2023
Language difficulties can make it challenging to communicate effectively in any language, including retrieving and using words that are spoken, written or signed. Medical disorders and physical trauma can disrupt a person’s ability to understand language and use it efficiently to communicate with others.
Aphasia is medical terminology used to denote a full loss of language skills. But, language skills involve complex functions that occur while accessing different areas of the brain, so numerous subsets exist. For example, expressive aphasia is a type of language disorder that affects a person's primary ability to produce language.
Receptive aphasia, on the other hand, causes difficulty in understanding both written and spoken language. This type of loss of language skills occurs due to damage in an area that is responsible for language expression and comprehension causing the person to have problems with verbal and visual communications.
A partial loss of language of skills is called dysphasia but the scientific community primarily uses aphasia for when describing or discussing either level of language loss. Both conditions can occur suddenly following trauma from a stroke or head injury, or gradually due to a neurological disease or brain tumor.
Language Modalities Also Affect Children
Loss of language skills also extends to children. A mix of receptive and expressive language modalities can cause a child to struggle with both understanding the meaning of words as well as using words to express themselves. Speech therapy is commonly used to help the child improve comprehension while adopting alternative ways to communicate, such as gesturing with visual aids.
Children with developmental or spectrum disorders, such as autism, or behavioral disorders, such as ADHD (attention deficit hyperactivity disorder), may struggle with speech and language skills. An autistic child may speak a few words early on before stopping altogether, be slow in social development, or both. Toddlers that have trouble imitating sounds may prefer gestures over spontaneous vocalizations.
Although researchers do not fully understand what causes the condition, children with apraxia struggle with the motor coordination of speech and may be late-talkers. When a child suffers from apraxia, their brain has difficulty coordinating complex oral functions required to create sounds into syllables, syllables into words, and words into phrases. Developmental apraxia requires professional treatment in order for the child to communicate.
Speech, Word Finding, and Comprehension
One of the most obvious signs of aphasia is speech difficulties. During language development, children may struggle to think of the right word, use correct grammar or understand the meaning of what they heard or read. Whereas congenital aphasia in children can be present from birth, acquired aphasia is rarely diagnosed, and childhood aphasia differs significantly from adult loss of language skills. Trauma is the common cause of acquired aphasia in children.
During adulthood the fundamental problem with language loss is one of recovery or re-learning of a native language, but in childhood, reversing aphasia requires the acquisition and initial development of language. With adult aphasia, the person often struggles with pronouncing words correctly, using words inaccurately, or jumbling words together without the correct spacing of silence between sounds.
Adult Primary Progressive Aphasia
A specific type of adult aphasia, known as Primary Progressive Aphasia (PPA), leads to the gradual loss of verbal and written communication skills in adults. PPA is caused by a shrinking of certain lobes of the brain (left side of the frontal, temporal, or parietal). People with PPA may be able to use content words like nouns and verbs but face challenges in producing speech, naming objects or comprehending conversations. The three primary variants of adult PPA include:
1) Semantic PPA – People who struggle to find the right words, understand their meaning, or name people and objects may have semantic variant primary progressive aphasia. They may gradually use more general terms for specific things, such as saying “animal” instead of “cat”. Since language skills related to colors, shapes and numbers rely on a different area of the brain, the person will likely retain those abilities.
2) Nonfluent/Agrammatic PPA – As nonfluent/agrammatic PPA progresses, individuals face increasing difficulty with speech production. They may speak slower, use shorter phrases, and experience confusion with sounds for familiar words. Deciphering complex sentences and using proper grammar also becomes a challenge. Despite the decline in language skills, number recognition and emotion understanding usually remains intact.
3) Logopenic PPA – Individuals with logopenic PPA progressively struggle with formulating and expressing the words they intend to speak. As it worsens, there is a gradual decline in speed of speech. The cause of logopenic PPA is still unknown, but it is associated with the accumulation of proteins (amyloid and tau) in brain cells, similar to Alzheimer's disease. There is no cure but medications can help manage its symptoms.
With PPA often striking individuals under 65 years old and an estimated one in 100,000 people affected, a timely diagnosis is crucial. Around 40% of cases are linked to an unusual form of Alzheimer's disease that affects language skills rather than memory,. The remaining 60% are caused by frontotemporal lobar degeneration and responsible for half of all dementias in individuals under 65. It is worth noting that PPA presents differently depending on the underlying disease.
At ProLingo, we encourage everyone to monitor and protect their language skills. When it comes to the diagnosis of all types of aphasia, a brain MRI is invaluable. It can detect shrinking in specific brain areas and reveal conditions like strokes, tumors, or other brain disorders that affect speech and language. Medications, speech therapy, and adopting healthy lifestyle habits can help enhance brain health and overall well-being.