3.2.1 What is LANGUAGE?

The term  language refers to a system of conventional (shared) symbols by means of which people, as members of social or cultural groups, use to communicate. Language can be expressed via different modes (American Speech Language Hearing Association, Language in Brief, n.d.):

• Spoken (using speech)
• Manual (e.g., sign languages)
• Written (e.g., text or braille)
• Other methods (e.g., picture symbols)

Receptive language (or language comprehension) refers to understanding of information, knowledge and ideas communicated by others.
Expressive language (or language production) refers to the ability to convey information, knowledge and ideas to others.

Components of language may be described using:
1. Bloom & Lahey model (Bloom & Lahey, 1978): Form, Content, and Use
2. Language domains (American Speech Language Hearing Association, Language in Brief, n.d.): Phonology, Morphology, Syntax, Semantics, and Pragmatics

Meta-language (or meta-linguistic) awareness is the ability to think about and reflect upon language and use this thinking for effective learning. Meta-language includes the awareness of phonological/phonemic, morphological, syntactic, semantic, and pragmatic “rules” of language .

Literacy is a term used to refer specifically to language in written form.

Biological, cognitive, social, and environmental factors influence how language is learned and used.  A person with adequate language skills is able to comprehend and produce language to meet their social, cultural, and occupational needs. This includes abilities to across language domains, as well as an understanding of the human factors that influence language, such as motivation, cultural norms, and social roles.

3.2.2 Language disorder

Language disorder a significant difficulty comprehending, producing, and learning spoken language. Language disorder may affect domains of morphology, syntax, semantics, and/or pragmatics. Difficulty may occur in one or multiple language domains and typically also affects written language comprehension and production (Bishop et. al. 2017). Some people with language disorders may require alternative or augmentative communication (AAC) to support their communication.

People with language disorder may experience difficulties with:

• Comprehending and following spoken and written instructions.
• Putting words into sentences when speaking or writing, for example, saying “He run” instead of “He is running”.
• Learning, comprehending, and understanding new words, for example, has a small “vocabulary” or uses words with incorrect meaning.
• Following conversations or understanding stories.
• Organising and sequencing information when telling or writing stories.
• Understanding social conventions or non-verbal language.

LANGUAGE DISORDER ASSOCIATED WITH BIOMEDICAL CONDITIONS

Language disorder may be associated with a biomedical or condition, for example, intellectual disability, Autism, acquired brain injury, or genetic conditions such as Down Syndrome. In these cases the term ‘language disorder associated with ‘biomedical condition’ is used.

Developmental LANGUAGE DISORDER (DLD)

Developmental Language Disorder (DLD) is the term used to describe language difficulties that are not associated with another biomedical condition (Bishop et al., 2017; The DLD Project, n.d.)

Developmental Language Disorder is a learning disability that:
1. Is present from an early childhood (i.e., neurodevelopmental disorder).
2. Is persistent across the lifespan (i.e., is ongoing in nature).
3. Has a functional impact (i.e., impacts on a person’s ability to perform daily activities or participate in daily life, school, or work).
4. Is not attributed to another condition which is likely to impact on language development (e.g.,  intellectual disability or Autism).
5. Is not solely due to cultural and linguistic differences or lack of exposure to language (e.g., hearing loss).

DLD has historically been called by other terms such as specific language impairment (SLI),  primary language impairment (PLI), speech-language impairment, or language delay. However, an international consensus study in 2017 adopted the term “Developmental Language Disorder (DLD)” as the internationally accepted term.

DLD may co-occur with impairments in other areas of learning or behaviour, for example, anxiety or depression, Attention Deficit Hyperactivity Disorder (ADHD), word-decoding difficulties/Dyslexia, or speech sound disorders.

Further information on DLD is provided on the Raising Awareness of Developmental Language Disorder Organisation Factsheet: DLD-Fact-Sheet-V3_original-2023.pdf

Below is a video about Developmental Language Disorder (DLD). This video is produced by the Raising Awareness of Developmental Language Disorder organisation.

^{DLD 1-2-3 by RADLD}

3.2.3 WORD DECODING DIFFICULTIES (DYSLEXIA)

Word decoding difficulty is a term used to describe difficulty with word reading and spelling due to deficits within the phonological processing system (i.e., phonological and phonemic awareness difficulties). The term dyslexia is also often used to describe word decoding difficulties (Dyslexia SPELD Foundation, n.d.)

People with word decoding difficulty (dyslexia) have difficulties with phonological awareness, phonemic awareness, and sound-letter correspondence. This may result in difficulties reading and spelling single words and comprehending and producing written language.

Phonological awareness is a meta-language skills that involves the ability to recognise and manipulate parts of sentences and words. For example:

• Segmenting words into syllables, for example, identifying that the word “caterpillar” has 4 syllables.
• Identifying words that rhyme, for example, identifying that/brʌʃ/ rhymes with /krʌʃ/.

Phonemic awareness is a meta-language skill that involves the ability to recognise and manipulate individual phonemes (sounds) in words. For example:

• Identifying phonemes in words, for example, identifying that the word /brʌʃ/ ends in the phoneme /ʃ/.
• Blending phonemes to make words, for example, identifying that the single phonemes /b/ /r/ /ʌ/ /ʃ/ combine to make the word /brʌʃ/.
• Segmenting words into phonemes, for example, identifying that the word /brʌʃ/ has 4 phonemes.
• Manipulating phonemes in words, for example, identifying that swapping the phoneme /b/ to /k/ changes the word /brʌʃ/ to /krʌʃ/.

Sound-letter correspondence is the ability to link spoken sounds (phonemes) to written letters (graphemes). For example:

• Identifying that the letters “sh” spell phoneme /ʃ/.
• Identifying that the letter “c” can represent phonemes /k/ or /s/.

Word decoding difficulty (dyslexia) is a learning disability that:
1. Is present from  an early (i.e., neurodevelopmental disorder).
2. Is persistent across the lifespan (i.e., is ongoing in nature).
3. Has a functional impact (i.e., impacts on a person’s ability to perform daily activities or participate in daily life, school, or work).
4. Is not attributed to another conditions which may affect reading and spelling (e.g., hearing loss or low vision).

Word decoding difficulties (Dyslexia) may also co-occur with impairments in other areas of learning or behaviour, for example: anxiety or depression, Attention Deficit Hyperactivity Disorder (ADHD), speech sound impairments, or language disorder.

Below is a video about word decoding/dyslexia. This video is produced by the Dyslexia – SPELD Foundation.

^{Understanding dyslexia by DSF Literacy and Clinical Services}

3.2.4 Acquired Language Disorders

In the sections above, you have learned about language processing and language disorders mainly from a developmental perspective.  However, some people may experience neurological injury and damage to the language centres of the brain that results in acquired language disorders.  The main acquired language disorder is aphasia.

Aphasia

Aphasia is an acquired language disorder caused by neurological injury to the language centres in the brain.  This damage may be caused by stroke, head injury, brain tumor, or neurodegenerative disease (e.g. dementia). Aphasia may affects a person’s ability to speak, understand language, read, and write (Papathanasiou & Coppens, 2022).

The video below provides a summary of aphasia.

^{Aphasia – the disorder that makes you lose your words by TED-ed}

There are different presentations or types of aphasia.  These presentations are generally classed as fluent (e.g. Broca’s aphasia; global aphasia; transcortical motor aphasia) or non-fluent (Wernicke’s aphasia transcortical sensory aphasia; conduction aphasia; anomic), dependent on which language areas of the brain have been affected.

The video below provides an outline of the fluent types of aphasia.

^{Fluent Aphasias made easy: How to distinguish and remember them! by Med School Made Easy}

The video below provides an outline of the non-fluent types of aphasia.

^{Non-fluent Aphasias made easy: How to distinguish and remember them! by Med School Made Easy}