4. Neuropsychology of the developing brain

Development of the cellular system?

cell birth → cell migration → cell differentiation, cell maturation → synaptogenesis → cell death and synaptic purging → myelogenesis

prenatal development risk factors?

maternal stress

maternal health

nutrition

maternal drug and alcohol addiction

environmental toxins

postnatal development risk factors?

birth complications

nutrition

environmental toxins

cerebral infection

environmental experience

developmental dimensions?

neuronal dimensions

cognitive dimensions

psycho-social dimension

effects of a neurological insult?

CNS injury → primary brain dysfunction, neuropsychological impairment, psychosocial disturbance → ongoing influence on development → abnormal brain development, neuropsychological impairment, psychosocial disturbance → outcome: generalized CNS problem, cognitive and social impairment

Sensorimotor stage?

birth to 18-24 months

experiences the world through senses and actions

Preoperational stage?

2-6 years

represents things w. words and images but lacks logical reasoning

Concrete operational stage?

7-11 years

thinks logically about concrete events, grasps concrete analogies and perfirms arithmetical operations

Formal operational stage?

ca 12+ years

reason abstractly

Attention-deficit / hyperactivity disorder (ADHD)?

developental disorder

distinguished from other types of learning disabilities in that an affected child has a behavioral problem in school, and all aspects of school performance are usually disrupted

prevalence: 5:1 boys, 9:1 girls

Diagnostic criteria of ADHD?

Excessive general hyperactivity or motor restlessness for the child’s age. The activity differs from norms for the age both quality and quantity

Diffficulty in sustaining attention, such as inability to complete tasks initiated or disorganized approach to tasks. The child frequently “forgets” demands made or tasks assigned and shows poor attention in unstructured situations of when demands are made for independent, unsupervised performance

impulsive behavior

duration of at least 1 year

ADHD symptoms?

In infancy, hyperactive children are thought to exhibit poor and irregular sleep, and feeding problems

By the time they reach kindergarten: they are demanding, do not listen, and do not play well with other children

By adolesence: many of these children are failing in school

Adult ages: from 25-50% of them have begun to encounter problems w. law. Their behavior remains restless, they withdraw from school, and they fail to develop social relations and maintain steady employment

ADHD causes?

nevertheless, this is one of the psychiatric problems w. large heritability. The genetic background is complex, polygenic

many brain anomalies are revealed by imaging studies. for example, decreased gray matter volume in the fronto-striatal system

prenatal passive smoking is an often mention cause, but the direct effect is weakly evidenced

low birth weight, preterm birth seem to be a risk factor

metabolic deficits (zinc, iron, fatty acid). studies, however, do not have consistent results

experience w. early family neglect seems to be important

Autism prevalence?

2000: 40-50 / 10.000 birth

gender difference: 3 (boys) : 1 (girls)

Autism?

the most extensively investigated developmental disorder

high prevalence

many human specific abilities can be impaired: language, mentalization ability and reciprocal social interaction

triad of impairments: reciprocal social interactions, mentality and reciprocal communication

Autism - deficit in reciprocal social interactions?

most salient aspect of autism

the child avoids physical contacts, other way around, accepts anything from anybody without selection

does not make any effort in sharing his/her experiences, emotions w. others

both the expression and the detection of emotions are impaired

does not show solidarity

does not want to have company

people = objects

Autism - deficit in reciprocal communication?

the language based communication is impaired

delayed language development

the deficit is already present at the level of pre-verbal communication

does not try to compensate their verbal communication inability

a part of the autistic persons have formally well developed verbal abilities, but the emotional tone is always missing from their conversations

repetitive verbal terms

autism - deficits in mentality and imagination?

rigid, repetitive and stereotype behavior, very narrow field of intrest

poor, and repetitive playing behavior

compulsatory behavior

narrow field of interest

non triad features of autism?

altered sensory processes

→ atypical sensory sensitivity

→ atypical sensory integration

Irregular ability profile

→ extreme fluctuation between various abilities

CNS causes in autism?

medial temporal lobe

frontal areas

changes to the brain stem

fetal alchohol syndrom → cognitive and behavioral problems?

cognitive: slow intellectual development, learning difficulties, memory deficit, impaired motoric coordination

behavioral problems: hyperactivity, impulsivity, psycho-social problems

→ alchohol-induced abnormalities can range from hardly noticeable physical and psychological effects to the full-blown FAS syndrome. The severity is thought to be related to when, how much and how frequently alcohol is consumed in pregnancy