Neurodevelopmental Disorders

Neurodevelopmental Disorders

Developmental deficits that impair personal, social, academic, and/or occupational functioning and usually begin early in development (before the child starts school)

Intellectual Developmental Disorder (Intellectual Disability)

The person must have:

-Deficits in intellectual functioning as determined by the results of a clinical assessment and individualized, standardized intelligence testing

-Deficits in adaptive functioning that cause a failure to meet developmental and socio-cultural standards for personal independence and social responsibility

-Onset of deficits during the developmental period

Intelligence testing scores as related to intellectual disability

Ordinarily obtain a score that is two or more standard deviations below the population mean on a standardized intelligence test

Specifiers for intellectual disability

-Used to indicate level of severity: mild, moderate, severe, or profound

-Based on adaptive functioning in conceptual, social, and practical domains

-Useful for determining the amount of support the person needs

Prevalence of causes of intellectual disability

-Cause is known in 25 to 50% of all cases

-Of cases with a known etiology:

About 80 to 85% are due to prenatal factors (which includes chromosomal and other genetic causes).

5 to 10% are due to perinatal factors (asphyxia).

5 to 10% are due to postnatal factors

-Most common chromosomal causes are Down's syndrome, followed by fragile X syndrome

-Most common preventable prenatal cause is fetal alcohol syndrome

Autism Spectrum Disorder (ASD)

-Deficits in social communication and social interaction across multiple contexts

-Restrictive and repetitive patterns of behaviors, interests, and activities

Deficits in social communication and social interaction

-Impaired social-emotional reciprocity - little or no initiation of social interaction, no sharing of emotions, difficulty processing and responding to social cues

-Impaired nonverbal communication that is used for social interaction - atypical use of eye contact, facial expressions, and gestures

-Impaired ability to develop, maintain, and understand relationships - atypical social interest, inappropriate approaches to others that seem aggressive or disruptive

Restrictive and repetitive patterns of behaviors, interests, and activities

-Stereotyped or repetitive motor movements, speech, or use of objects

-Insistence on sameness or inflexible adherence to routines

-Restricted or fixated interests that are abnormal in intensity or focus

-Hyper- or hyporeactivity to sensory input

Onset of ASD symptoms

Early developmental period

Factors that contribute to the best prognosis of ASD

-The person has an IQ over 70

-Functional language skills by age five

-Absence of comorbid mental health problems

Associated features of ASD

-Intellectual and language impairments, self-injurious behaviors (head banging), motor abnormalities (clumsiness, walking on tiptoes), and disruptive/challenging behaviors

-Impaired face recognition and emotion recognition, which have been identified as contributors to deficits in social relationships

Prevalence rates of ASD

-Rates in the US and other countries vary - most range from 1 to 2% of the population

-Diagnosed 3-4x more often in males than in females

Etiology of ASD

-Unknown

-Believed to be due to multiple genetic and non-genetic factors

Concordance Rates of ASD

-Monozygotic twins range from 69 to 95%

-Dizygotic twins range from 0 to 24%

Non-genetic risk factors of ASD

-Male gender

-Birth before 26 weeks of gestation

-Advanced parental age

-Exposure to certain environmental toxins during prenatal development

Link between ASD and neurotransmitter abnormalities

-Accelerated brain growth in children with ASD that begins at about 6 months of age and plateaus by the preschool years - corresponds to a larger-than-normal head circumference and increased brain volume and weight during that period

-Abnormalities found in the cerebellum, corpus callosum, and amygdala

-Often have lower-than-normal levels of serotonin in several areas of the brain but elevated levels of serotonin in the blood

-Other neurotransmitters - dopamine, GABA, glutamate, and acetylcholine

Primary tx goals for ASD

-Minimize the core symptoms of the disorder

-Maximize independence by promoting the acquisition of functional skills

-Reduce or eliminate behaviors that may interfere with functional skills

Nonpharmacological interventions of ASD

-Early intensive behavioral intervention (EIBI) is an evidence-based treatment that uses the principles and techniques of applied behavior analysis (ABA)

Benefits of Early Intensive Behavioral Intervention (EIBI)

-Providing young children with at least 40 hours per week of behavioral interventions and using shaping and discrimination training to teach nonspeaking children to communicate verbally

-It has the greatest positive impact on intelligence and language acquisition and a smaller and less consistent impact on adaptive skills, social functioning, and severity of core ASD symptoms

Pharmacological tx of ASD

-No medication has been found to be effective for the core symptoms

-Medications are ordinarily prescribed for co-occurring psychiatric conditions and associated behaviors that cause distress but are not addressed by or haven't been alleviated by nonpharmacological interventions

ADHD

A pattern of inattention and/or hyperactivity-impulsivity that has persisted for at least six months, had an onset before 12 years of age, is present in at least two settings, and interferes with social, academic, or occupational functioning

Dx requirements of ADHD

At least six6symptoms of inattention and/or at least 6 symptoms of hyperactivity-impulsivity (or at least 5 symptoms for individuals age 17 and older)

Inattention Symptoms

-Doesn't listen when spoken to

-Fails to pay close attention to details

-Doesn't follow through on instructions

-Easily distracted by extraneous stimuli

-Often forgetful in daily activities

Hyperactivity-Impulsivity Symptoms

-Unable to engage in play or leisure activities quietly

-Often runs or climbs in inappropriate situations

-Talks excessively

-Trouble waiting their turn

-Interrupts or intrudes on others

ADHD Specifiers

-Predominantly inattentive presentation

-Predominantly hyperactive/impulsive presentation

-Combined presentation

Prevalence of ADHD

-Most prevalent diagnosed disorder among youth ages 3 to 17 years

-Gender - 2x more common in males than females during childhood

-Gender difference decreases somewhat in adulthood when the ratio of males to females is about 1.6:1

-Estimates of the persistence of ADHD into adulthood vary, but there is evidence that the majority of children with ADHD continue to experience one or more core symptoms as adults

ADHD symptom changes in adulthood

-The excessive motor activity decreases and is replaced by an inability to relax or sit still, impatience, and a sense of restlessness

-Impulsivity decreases slightly and changes to include driving recklessly, abruptly quitting jobs and ending relationships, and overspending

-Inattention continues during adulthood and involves an inability to meet important deadlines, making careless mistakes, and procrastination, and it is most apparent for boring and tedious (versus novel or interesting) tasks

Comorbidity in ADHD

-Reported rates of specific comorbid disorders vary somewhat

-Oppositional defiant disorder is the most common comorbid disorder followed by, in order, conduct disorder, an anxiety disorder, and a depressive disorder

Brain Abnormalities in ADHD

Linked to various structural and functional brain issues.

Result of abnormalities in the prefrontal cortex, striatum (caudate nucleus and putamen), and thalamus

Impaired response inhibition, working memory, sustained attention, and other aspects of executive functioning

Result of abnormalities in the prefrontal cortex and cerebellum

Impaired temporal information processing (inability to perceive and organize sequences of events and anticipate when future events will occur)

Result of abnormalities in the prefrontal cortex and amygdala

Emotion dysregulation

Result of reduced total brain volume

Smaller-than-normal volumes in the prefrontal cortex, striatum, corpus callosum, and cerebellum, and reduced activity in these regions

Neurotransmitter abnormalities in ADHD

-Low levels of dopamine and norepinephrine have most consistently been identified as contributors to the cognitive and behavioral symptoms of ADHD

-Low levels of these neurotransmitters in the prefrontal cortex have been linked to impairments in impulse control, attention, and executive functioning.

Genetic contribution of ADHD

One of the most heritable psychiatric disorders, with the mean heritability estimate across twin studies being 76%

Concordance rates of ADHD

Average is 71% for monozygotic twins, 41% dizygotic.

Factors linked to ADHD

-Low birth weight

-Premature birth

-Maternal smoking or alcohol use during pregnancy

ADHD interventions for preschoolers

-Parent- and teacher-administered behavioral interventions are the treatment-of-choice

-Evidence-based parent training in behavioral management (PTBM) being the primary recommended intervention

-Positive parenting program and parent-child interaction therapy (PCIT)

-Medication is prescribed only when behavioral interventions do not produce adequate improvement

ADHD interventions for elementary and middle schoolers

Combination of medication and behavioral interventions at home and at school

ADHD interventions for adolescents

-Prescribe medication with the adolescent's assent and to combine medication with behavioral and instructional interventions when they are available

-Evidence that adolescents may benefit from behavioral therapy, motivational interviewing, mindfulness-based training, and classroom training

ADHD interventions for adults

-First-line treatment is medication

-Psychosocial interventions have been found to have beneficial effects

-CBT has the strongest support

Stimulant use in children vs substance use as adults

-While ADHD in childhood has been linked to an increased risk for substance use problems in adolescence and adulthood, the research suggests this link is not due to treatment with a psychostimulant in childhood

-Children who do and do not receive a psychostimulant drug are comparable in terms of rates of future substance-related problems

-Treatment during childhood with a psychostimulant neither decreases nor increases the risk for later substance use disorders

Tic disorder

Sudden, rapid, recurrent motor movement or vocalization.

Motor tics

Eye blinking, facial grimacing, shoulder shrugging, and echopraxia

Vocal tics

Throat clearing, barking, and echolalia

Tourette's disorder

-At least 1 vocal tic and multiple motor tics that may occur together or at different times

-May wax and wane in frequency but have persisted for more than 1 year

-Had an onset before 18 years of age

Persistent (chronic) motor or vocal tic disorder

-1 or more motor or vocal tics

-Persisted for more than 1 year

-Began before age 18

Provisional tic disorder

-1 or more motor and/or vocal tics

-Been present for less than 1 year

-Began before age 18

Onset of tics

Typically occurs between 4 and 6 years of age.

Peak severity of tics

Ordinarily peaks between 10 and 12 years.

Comorbidities of Tourette's

Often co-occur with other psychiatric disorders, with ADHD being the most common

Neurotransmitter linked to tourette's

Dopamine overactivity, a smaller-than-normal caudate nucleus, and heredity

Pharmacological tx for tics

-Antipsychotic drug (haloperidol)

-Medication for comorbid conditions

-Serotonin for obsessive-compulsive symptoms

-Methylphenidate or clonidine for ADHD

Behavioral tx for tourette's

Comprehensive behavioral intervention for tics (CBIT) - consists of psychoeducation, social support, and habit reversal, competing response, and relaxation training

Childhood-onset fluency disorder (stuttering)

-A disturbance in normal fluency and time patterning of speech that's inappropriate for the person's age and language skills

-Persists over time

Symptoms of stuttering

-Sound and syllable repetitions

-Sound prolongations

-Broken words

-Audible or silent blocking

-Circumlocutions

-Words pronounced with excessive physical tension

-Monosyllabic whole-word repetitions

Onset of stuttering

Usually between 2 and 7 years of age

Recovery from dysfluency

65 to 85% of children recover by age 8.

Treatment of choice for tourette's

Habit reversal training which incorporates several strategies including competing response training that, for this disorder, is regulated breathing

Specific Learning Disorder

Difficulties related to academic skills as indicated by the presence of at least 1 of 6 symptoms that last for at least 6 months despite the use of interventions that address difficulties

Symptoms of Specific Learning Disorder

-Inaccurate or slow and effortful word reading

-Difficulty understanding the meaning of what is read

-Difficulties with spelling

-Difficulties with written expression

-Difficulties mastering number sense, number facts, or calculation

-Difficulties with mathematical reasoning

Diagnosis criteria for learning disorder

-Requires academic skills must be substantially below those expected for a person's age

-Interfere with academic or occupational performance or activities of daily living

-Have an onset during the school-age years

-Not better accounted for by another disorder or condition (uncorrected visual or auditory impairment)

Specifiers of specific learning disorders

Used to indicate subtype (with impairment in reading, with impairment in written expression, or with impairment in mathematics) and level of severity

Prevalence of learning disabilities

-5 to 15% of school-age children have a specific learning disability

-About 80% of these children have a reading disorder

Most common reading disorder

Dyslexia

Most common type of dyslexia

Dysphonic

Dysphonic dyslexia

-Involves difficulties connecting sounds to letters

-Also known as dysphonetic, auditory, and phonological

Comorbidities with specific learning disorder

-Usually have an average to above-average IQ

-ADHD to be the most common comorbid psychiatric disorder