Ch 24 - Neurodevelopmental Disorders

neurodevelopmental disorders used to be called

learning disabilities

neurodevelopmental disorders are defined as beginning between ___ and ___

in utero development and the start of formal schooling

why are neurodevelopmental disorders hard to identify?

deficits often emerge gradually

common assessment standard is performance ___ behind expected

2 years (based on age)

intellectual disability is defined as

not being able to learn and perform at the expected level

how are intellectual disabilities assessed?

by standardized testing of IQ and adaptive behaviors

what is the primary characteristic of cerebral palsy?

motor abnormalities

cerebral palsy usually stems from

head trauma during delivery or development

cerebral palsy treatment

CP is not reversible (or progressive), but motor symptoms improve with physical therapy

what are the types of cerebral palsy? which is most common?

spastic, athetoid, rigidity, ataxic

(listed in order of most to least common, spastic is most common)

spastic cerebral palsy

limbs resist being moved

athetoid cerebral palsy

slow involuntary movements

rigidity cerebral palsy

muscles around joints are stiff

ataxic cerebral palsy

difficulty making voluntary movements

hydrocephalus

increased volume of CSF on the brain (can be seen as expanded ventricles

hydrocephalus cause

obstructed flow somewhere in the ventricular system

hydrocephalus

shunt can drain the fluid, normally really well recovery of function and tissue displacement

most common inherited cause of mental impairment

fragile-X syndrome

what is fragile X syndrome? genetic component, characteristic signs

genetic disorder in the FMR1 gene on the X chromosome. characterized by facial abnormalities, intellectual impairment

what are the effects of fragile X syndrome on the brain? what is thought to be the developmental cause?

poorly formed (and too many) dendritic spines, thought to be a pruning problem. this results in thinned cortex, small caudate, and large ventricles.

fragile x syndrome is more common and more severe in (men/women). why?

more common and severe in men, because women have 2 X chromosomes and can adapt.

characteristic traits of fetal alcohol spectrum disorder?

intellectual impairments, learning disabilities, hyperactivity, social problems, physical malformations

FASD causes

alcohol use before conception (either parent) or during pregnancy. alcohol impacts cell division and maturation, so many developmental implications there

how are FASD brains different?

smaller, abnormal gyri, abnormal clusters of cells

down syndrome is cause by

an extra copy of chromosome 21

characteristics of down syndrome

intellectual and developmental disabilities (ranging from mild to severe), shortened life expectancy. may increase risk of health problems. increased chance of Alzheimer’s

how are communication disorders defined?

Disorders of speech and language that range in severity from sound substitution to inability to comprehend language

how are language and speech sound disorder different?

language disorder - difficulties learning and using spoken, written, or sign language

speech sound disorder - difficulties pronouncing or articulating the native language

language disorder treatments

speech and language therapy (disorder tends to be stable over time and persists into adulthood)

For typically developing children, about half of speech sounds should be intelligible by age ___ and most should be intelligible by age ___`

2, 4

speech sound disorder treatments

speech and language therapy (usually very beneficial for speech sound disorder!)

childhood-onset fluency disorder

(previously stuttering) repetition of words or syllables

childhood-onset fluency disorder is most of the time resolved…

spontaneously in childhood (or with speech therapy)

treatment for childhood-onset fluency disorder

speech therapy

what is it called when childhood-onset fluency disorder persists into adulthood?

persistent fluency disorder

social communication disorder

difficulty with the use of verbal and nonverbal communication in everyday situations. individuals have difficulty understanding implied meanings, metaphors, and humor. ruled out when diagnosing ASD

autism spectrum disorder

impaired social interaction, narrow interests, language and communication abnormalities

first signs of ASD develop…

between age 1 and 3

child insists on sameness and routine, failure to interact socially, repeated body movements. what may be suspected?

ASD

those with high functioning autism often also have what traits?

hyperlexia or an increased ability in math, art, or music, may develop speech earlier. milder social withdrawal

anatomical correlates of ASD

larger head and brain size, failure of von Economo neurons in cingulate to develop, overconnectivity within the PFC, underconnectivity from PFC to other lobes. brainstem abnormalities including smaller pons (this one is iffy)

what are the most likely causes of ASD?

microbiome, epigenetics, genetics (HOS1A gene)

ADHD diagnosis requires 

inattention and hyperactivity and impulsivity (present for at least a year)

___ may result in the inability to self-regulate behavior in ADHD

Impairment of the ventral frontal circuits, including the basal ganglia

patients with ADHD have decreased gray matter in

orbitofrontal areas

___ problem is most common finding and points to problems with executive function in ADHD

prefrontal and basal ganglia

ADHD effective treatments

multimodal combinations of behavioral/psychosocial therapy and medication

encephalitis

swelling of brain from infection

how are specific neurodevelopmental learning disorders different from intellectual disability?

generally have average intelligence, but usually a difficulty in learning or using a particular academic skill

reading requires… (5)

phonological skills, grapheme skills, sequencing skills, short term memory, and lexicon

___ reading decodes the letters of the words into sounds that can be pronounced

phonological

___ reading looks at the whole word and produces the sound of that word from memory

graphemic

what are the potential causes of reading disorders? (4)

phonological and sensory deficiency

attentional deficiency

motor deficiency

multicausal approaches

individuals with reading disorders caused by phonological and sensory deficiency have a problem with what brain area?

L hemi language regions

individuals with reading disorders caused by attentional deficiency have a problem with what brain area?

association areas of the parietal lobe

how can attentional deficiency in reading disorders be remediated?

by sound discrimination training

what is magnocellular theory in reading disorders?

postulates that reading difficulties originates in the magnocellular part of the visual system which processes B&W vision and movement (words may appear to move or jump around)

magnocellular theory is an idea that the ___ and ___ dont integrate properly

dorsal and ventral pathways

individuals with reading disorders caused by a motor deficiency have a problem with what brain area?

cerebellum

Difficulty representing and processing numbers in a typical way

mathematical disabilities

difficulty separating left and right and trouble recognizing patterns can also be symptoms of 

mathematical disabilities

___ tests are commonly used to assess overall cognitive function

IQ

what is the ACID profile?

arithmetic, coding, information, digit span. it is a part of the Weschler intelligence scale for children, suggests a specific learning impairment

how are learning disorders evaluated?

IQ test for overall cognitive function, but not used for specific disabilities. from there, additional specific tests are used to identify particular impairments.

developmental coordination disorder

Disturbances of gross and fine motor control, such as timing, balance, sequences of movements, and remembering movements. can co-occur with ADHD or ASD

what factors can lead to developmental disorders?

structural damage and toxic effects, hormonal effects, environmental deprivation

what is the birthday effect?

the idea that maturational age could aggravate performance in developmentally disabled children; individuals born earlier in the year will be bigger and more mature than individuals born later that same year