Nonverbal learning disorder

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Nonverbal learning disorder
Other namesNonverbal learning difficulties
Specialty Neurology/psychiatry
FrequencyCurrently unknown, estimated to be around 3% [1]

Nonverbal learning disability (NVLD) is a proposed category of neurodevelopmental disorder characterized by core deficits in visual-spatial processing and a significant discrepancy between verbal and nonverbal intelligence (where verbal intelligence is higher). [2] A review of papers found that proposed diagnostic criteria were inconsistent. [2] Proposed additional diagnostic criteria include intact verbal intelligence, and deficits in the following: visuoconstruction abilities, speech prosody, [3] fine motor coordination, mathematical reasoning, visuospatial memory and social skills. [4] [5] [6] [7] NVLD is not recognised by the DSM-5 and is not clinically distinct from learning disorder. [8]

Contents

NVLD's symptoms can overlap with symptoms of autism spectrum, bipolar disorder, and ADHD. For this reason, some claim a diagnosis of NVLD is more appropriate in some subset of these cases. [3] [9]

Signs and symptoms

Using an analog clock to tell time is difficult for people with symptoms of NVLD. Modern functual kept battery driven wall clock.jpg
Using an analog clock to tell time is difficult for people with symptoms of NVLD.

Considered to be neurologically based, [10] [11] nonverbal learning disorder is characterized by:

People with NVLD may have trouble understanding charts, reading maps, assembling jigsaw puzzles, and using an analog clock to tell time. "Clumsiness" is common in people with NVLD, especially children, and it may take a child with NVLD longer than usual to learn how to tie shoelaces or to ride a bicycle. [9]

At the beginning of their school careers, children with symptoms of NVLD struggle with tasks that require eye–hand coordination, such as coloring and using scissors, but often excel at memorizing verbal content, spelling, and reading once the shapes of the letters are learned. A child with NVLD's Average or Superior verbal skills can be misattributed to attention deficit hyperactivity disorder, defiant behavior, inattention, or lack of effort. [9] Early researchers in the syndrome of NVLD Johnson and Myklebust characterize how the children appear in a classroom: "An example is the child who fails to learn the meaning of the actions of others [...] We categorize this child as having a deficiency in social perception, meaning that he has an inability which precludes acquiring the significance of basic nonverbal aspects of daily living, though his verbal level of intelligence falls within or above the average." [12]

In the adolescent years, when schoolwork becomes more abstract and the executive demands for time management, organization, and social interactions increase, students with NVLD begin to struggle. They focus on separate details and struggle to summarize information or to integrate ideas into a coherent whole, and they struggle to apply knowledge to other situations, to infer implicit information, to make predictions, and to organize information logically. [9]

As adults, tasks such as driving a car or navigating to an unfamiliar location may be difficult. Difficulty with keeping track of responsibilities or managing social interactions may affect job performance. [9]

People with NVLD may also fit the diagnostic criteria of dyscalculia, [13] [14] dysgraphia, [15] [16] [17] or dyspraxia. [18] [19]

Cause

Research suggests that there is an association with an imbalance of neural activity in the right hemisphere of the brain connected to the white matter. [10]

Diagnosis

Nonverbal learning disability (NVLD) is characterized by core deficits in visualspatial processing and social impairment. [10] Additional proposed diagnostic criteria include average to superior verbal intelligence and deficits in visuoconstruction abilities, fine motor coordination, mathematical reasoning, visuospatial memory and social skills. [5]

"While NVLD is not classified into any distinct diagnosis in DSM-5 (American Psychiatric Association, 2013) or ICD-10 (World Health Organization, 1992), it does have a robust research base." [20] [21] [22] "The majority of researchers and clinicians agree that the profile of NLD clearly exists [...] but they disagree on the need for a specific clinical category and on the criteria for its identification." (One researcher notes: "just because we cannot reasonably place such children into our present classification scheme does not mean they do not exist." [23] )

Assorted diagnoses have been discussed as sharing symptoms with NVLD. In some cases, especially the form of autism previously called Asperger syndrome, the overlap can be significant; a major clinical difference is that NVLD criteria do not mention the presence or absence of either repetitive behaviors or narrow subject-matter interests, [9] which is part of the diagnostic criteria for autism. [24] These overlapping conditions include, among others:

There is diagnostic overlap between nonverbal learning disorder and autism spectrum, and some clinicians and researchers consider them to be the same condition. [9] [7] Some claim that some diagnoses of attention deficit hyperactivity disorder would be more appropriately classified as NVLD. [9]

History

While various nonverbal learning difficulties were recognized since early studies in child neurology, [33] there is ongoing debate as to whether/or the extent to which existing conceptions of NVLD provide a valid diagnostic framework. [34] [35]

As presented in 1967, "nonverbal disabilities" (p. 44) or "disorders of nonverbal learning" was a category encompassing non-linguistic learning problems. [12] "Nonverbal learning disabilities" were further discussed by Myklebust in 1975 as representing a subtype of learning "disability" with a range of presentations involving "mainly visual cognitive processing," social imperception, a gap between higher verbal ability and lower nonverbal processing, as well as difficulty with handwriting. [36] Later neuropsychologist Byron Rourke [37] sought to develop consistent criteria with a theory and model of brain functioning that would establish NVLD as a distinct syndrome (1989). [38]

Questions remain about how best to frame the perceptual, cognitive and motor issues associated with NVLD. [11] [39] [40] [5]

See also

Related Research Articles

<span class="mw-page-title-main">Asperger syndrome</span> Neurodevelopmental diagnosis now categorized under Autism Spectrum Disorder

Asperger syndrome (AS), also known as Asperger's syndrome, formerly described a neurodevelopmental disorder characterized by significant difficulties in social interaction and nonverbal communication, along with restricted and repetitive patterns of behavior, interests, and activities. The syndrome has been merged with other disorders into autism spectrum disorder (ASD) and is no longer considered a stand-alone diagnosis. It was considered milder than other diagnoses that were merged into ASD due to relatively unimpaired spoken language and intelligence.

The diagnostic category pervasive developmental disorders (PDD), as opposed to specific developmental disorders (SDD), was a group of disorders characterized by delays in the development of multiple basic functions including socialization and communication. It was defined by the Diagnostic and Statistical Manual of Mental Disorders (DSM), and the International Classification of Diseases (ICD).

Dyscalculia is a disability resulting in difficulty learning or comprehending arithmetic, such as difficulty in understanding numbers, learning how to manipulate numbers, performing mathematical calculations, and learning facts in mathematics. It is sometimes colloquially referred to as "math dyslexia", though this analogy is misleading as they are distinct syndromes.

Developmental disorders comprise a group of psychiatric conditions originating in childhood that involve serious impairment in different areas. There are several ways of using this term. The most narrow concept is used in the category "Specific Disorders of Psychological Development" in the ICD-10. These disorders comprise developmental language disorder, learning disorders, motor disorders, and autism spectrum disorders. In broader definitions ADHD is included, and the term used is neurodevelopmental disorders. Yet others include antisocial behavior and schizophrenia that begins in childhood and continues through life. However, these two latter conditions are not as stable as the other developmental disorders, and there is not the same evidence of a shared genetic liability.

Multisystem developmental disorder (MSDD) is a term used by Stanley Greenspan to describe children under age 3 who exhibit signs of impaired communication as in autism, but with strong emotional attachments atypical of autism. It is described in the DC:0-3R manual as an optional diagnosis for children under two years of age.

Pervasive developmental disorder not otherwise specified (PDD-NOS) is a historic psychiatric diagnosis first defined in 1980 that has since been incorporated into autism spectrum disorder in the DSM-5 (2013).

Mixed receptive-expressive language disorder is a communication disorder in which both the receptive and expressive areas of communication may be affected in any degree, from mild to severe. Children with this disorder have difficulty understanding words and sentences. This impairment is classified by deficiencies in expressive and receptive language development that is not attributed to sensory deficits, nonverbal intellectual deficits, a neurological condition, environmental deprivation or psychiatric impairments. Research illustrates that 2% to 4% of five year olds have mixed receptive-expressive language disorder. This distinction is made when children have issues in expressive language skills, the production of language, and when children also have issues in receptive language skills, the understanding of language. Those with mixed receptive-language disorder have a normal left-right anatomical asymmetry of the planum temporale and parietale. This is attributed to a reduced left hemisphere functional specialization for language. Taken from a measure of cerebral blood flow (SPECT) in phonemic discrimination tasks, children with mixed receptive-expressive language disorder do not exhibit the expected predominant left hemisphere activation. Mixed receptive-expressive language disorder is also known as receptive-expressive language impairment (RELI) or receptive language disorder.

Dyssemia is a difficulty with receptive and/or expressive nonverbal communication. The word comes from the Greek roots dys (difficulty) and semia (signal). The term was coined by psychologists Marshall Duke and Stephen Nowicki in their 1992 book, Helping The Child Who Doesn't Fit In, to decipher the hidden dimensions of social rejection. These difficulties go beyond problems with body language and motor skills. Dyssemic persons exhibit difficulties with the acquisition and use of nonverbal cues in interpersonal relationships. "A classic set of studies by Albert Mehrabian showed that in face-to-face interactions, 55 percent of the emotional meaning of a message is expressed through facial, postural, and gestural means, and 38 percent of the emotional meaning is transmitted through the tone of voice. Only seven percent of the emotional meaning is actually expressed with words." Dyssemia represents the social dysfunction aspect of nonverbal learning disorder.

Neurodevelopmental disorders are a group of conditions that begin to emerge during childhood. According to the American Psychiatric Association Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition, (DSM-5) published in 2013, these conditions generally appear in early childhood, usually before children start school, and can persist into adulthood. The key characteristic of all these disorders is that they negatively impact a person's functioning in one or more domains of life depending on the disorder and deficits it has caused. All of these disorders and their levels of impairment exist on a spectrum, and affected individuals can experience varying degrees of symptoms and deficits, despite having the same diagnosis.

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In psychology and neuroscience, executive dysfunction, or executive function deficit, is a disruption to the efficacy of the executive functions, which is a group of cognitive processes that regulate, control, and manage other cognitive processes. Executive dysfunction can refer to both neurocognitive deficits and behavioural symptoms. It is implicated in numerous psychopathologies and mental disorders, as well as short-term and long-term changes in non-clinical executive control. Executive dysfunction is the mechanism underlying ADHD Paralysis, and in a broader context, it can encompass other cognitive difficulties like planning, organizing, initiating tasks and regulating emotions. It is a core characteristic of ADHD and can elucidate numerous other recognized symptoms.

<span class="mw-page-title-main">Classic autism</span> Neurodevelopmental condition

Classic autism, also known as childhood autism, autistic disorder, (early) infantile autism, infantile psychosis, Kanner's autism,Kanner's syndrome, or (formerly) just autism, is a neurodevelopmental condition first described by Leo Kanner in 1943. It is characterized by atypical and impaired development in social interaction and communication as well as restricted, repetitive behaviors, activities, and interests. These symptoms first appear in early childhood and persist throughout life.

Pediatric neuropsychology is a sub-speciality within the field of clinical neuropsychology that studies the relationship between brain health and behaviour in children. Many pediatric neuropsychologists are involved in teaching, research, supervision, and training of undergraduate and graduate students in the field.

Several factors complicate the diagnosis of Asperger syndrome (AS), an autism spectrum disorder (ASD). Like other ASD forms, Asperger syndrome is characterized by impairment in social interaction accompanied by restricted and repetitive interests and behavior; it differs from the other ASDs by having no general delay in language or cognitive development. Problems in diagnosis include disagreement among diagnostic criteria, the controversy over the distinction between AS and other ASD forms or even whether AS exists as a separate syndrome, and over- and under-diagnosis for non-technical reasons. As with other ASD forms, early diagnosis is important, and differential diagnosis must consider several other conditions.

<span class="mw-page-title-main">Autism spectrum</span> Neurodevelopmental disorder

Autism, formally called autism spectrum disorder (ASD) or autism spectrum condition (ASC), is a neurodevelopmental disorder marked by deficits in reciprocal social communication and the presence of restricted and repetitive patterns of behavior. Other common signs include difficulties with social interaction, verbal and nonverbal communication, along with perseverative interests, stereotypic body movements, rigid routines, and hyper- or hyporeactivity to sensory input. Autism is clinically regarded as a spectrum disorder, meaning that it can manifest very differently in each person. For example, some are nonspeaking, while others have proficient spoken language. Because of this, there is wide variation in the support needs of people across the autism spectrum.

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The Children's Nonverbal Learning Disabilities Scale (C-NLD) is an assessment that screens for the symptoms for nonverbal learning disabilities in children, which can affect a child's visual spatial organization, motor abilities, and social interactions. All questions in the assessment are categorized in three headings: motor skills, visual-spatial skills, and interpersonal skills.

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Further reading

Books

By Authors with NVLD