Neurodevelopmental Flashcards
What is a neurodevelopmental disorder
A group of conditions that affect the development of the neurological system and brain, impacting different aspects of cognitive functioning. They can range from mild impairments to severe disorders and normally manifest in infancy or early childhood
The more mild it is, the less likely it is to be diagnosed later on.
What are some common neurodevelopmental disorders?
Autism, ADHD, Intellectual disabilities, learning disorders, communication disorders, motor disorders, tic disorders, conduct disorders, cerebral palsy
What are some possible causes of neurodevelopmental disorders?
Low birth weight, premature birth, environmental contaminants, fetal exposure to smoking, alcohol, drugs, or certain medications, and genetics
What is Autism Spectrum Disorder?
A spectrum of developmental disorders with a neurological basis in the brain, thought to be caused by a combination of genetic and environmental factors.
What are the symptoms of Autism Spectrum Disorder?
● Difficulties in social situations, communicating, and learning.
● Difficulty expressing emotions.
● Not understanding pretend play or abstract ideas.
● Does not speak or has delayed speech.
● Repetitive behavior.
● Resistant to hugging, cuddling, or other forms of touch.
● Little or no eye contact.
● Does not respond to name.
● Sensitivity to certain sounds, smells, or textures.
What are some brain abnormalities observed in Autism Spectrum Disorder?
● Larger than normal head and brain size. This may be due to atypical cell divisions, cell loss, and synaptic pruning (Larger head size seen at a year old).
● Larger number of frontal cortex cells, linked to abnormal social development.
● Cerebellar abnormality, linked to a desire for sameness and avoidance of novelty (repetitive behaviour)
● Fewer connections between brain regions and increased connections within the frontal area
Difficult with explicit memories: temporal lobe abnormalities
Difficult with implicit memories: parietal lobe abnormalities
Synaptic pruning may not happen = abnormal social development
What is ADHD?
A disorder defined by non-emotional symptoms including inattention, hyperactivity, and impulsivity. The cause of ADHD is uncertain, but is likely a combination of genetic and environmental factors.
What are the different subtypes of ADHD?
● Hyperactive-impulsive
● Inattentive
● Combined hyperactive-impulsive & inattentive
- Hyperactive tends to get diagnosed first because the symptoms are more disruptive
- Boys have hyperactive
- Girls have inattentive
What are some brain abnormalities observed in ADHD?
● Slower brain maturation compared to healthy individuals.
● Decreased gray matter volume in several regions including the insula, ventromedial prefrontal/medial orbito-frontal cortex, rostral and caudal anterior cingulate cortex, occipital lobe, amygdala, basal ganglia, and hippocampus. Note that some of these structural differences may disappear in adulthood.
What are intellectual disabilities?
A lifelong condition characterized by substantial cognitive and adaptive development delays owing to abnormalities of brain structure or function. It is a general symptom of neurological dysfunction, with the age of identification reflecting the degree of severity.
What causes intellectual disabilities?
There are several causes including prenatal, perinatal, and postnatal:
- Prenatal: infection, down syndrome
- Perinatal: during birth, prematurity or lack of oxygen
- Postnatal: brain injury, toxins
- Prenatal and genetic are the most common causes
What are the 3 main components of intellectual disabilities?
● Significantly below average intellectual functioning.
● Deficits or impairments in adaptive skills.
● Onset before 18 years of age.
What is Fragile X Syndrome, and what are some of its characteristics?
● A genetic disorder that causes intellectual disability, resulting in developmental delays, learning disabilities, social problems, and behavioral problems.
● Males with Fragile X typically have moderate ID but cognitive outcomes can vary, facial feature abnormalities, and behavioral characteristics including ADHD, mumbling speech pattern, hand biting or flapping, and autism-type behaviors.
● Females with Fragile X have milder cognitive and physical expressions of the disorder. They may or may not have physical features, and can exhibit behavioral characteristics including learning difficulties, attention problems, language dysfunction, autism spectrum disorders, affective and schizophrenia spectrum disorders.
What are some brain changes observed in Fragile X?
Cortical thinning, increased ventricular size, lower gray matter volume in some regions, reduced connectivity, and reduced functioning
What is Down Syndrome, and what are some of its characteristics?
● The most common genetic developmental disorder, affecting an individual throughout their life.
● Results in multiple health problems including intellectual disability, heart defects, hypothyroidism, and dementia.
● Cognitive deficits range from mild to severe.
