Human Development II Flashcards
What are the trends in Brain Development?
Brain is ~95% of adult size by age 6 – Importance of early intervention when
neurodevelopmental disorders are identified
• Two major changes occur throughout childhood, adolescence, and young adulthood:
1) Synaptic density shows an inverted U-shaped trajectory: Density increases until puberty then steady pruning throughout adolescence and adulthood
2) Continued myelination of certain brain regions
What’s the significance of synaptic density?
1) SYNAPTIC DENSITY
• Inverted U-shaped trajectory for gray matter volume
― Frontal and parietal gray matter peaks at age 12 in boys and 10 in girls (panels A & B)
― Later peak for temporal gray matter at age 16
White Matter • Linear increase in white matter volume (Panel D) ― Axons, myelin, glial cells ― Decline in white matter starts in ~40s
What’s the significance of myelination?
MYELINATION
• White matter myelination proceeds in a regionally-specific manner
― Earliest areas: primary motor and sensory
― Latest regions: prefrontal, temporal, and parietal association areas (up through at least 3rd decade)
― The development of more complex
cognitive functioning is supported by
regions with ongoing myelination
(particularly long-range association pathways and the frontal lobes)
What are the features of physical development in early childhood?
- Slow down in physical growth
- Decreased appetite
• Sphincter control (age3-5yrs)
– Bowel control problems ≥ age 4: Encopresis
– Bladder control problems ≥ age 5: Enuresis
• Improved gross motor and fine motor development
– Stacks blocks – age x 3
• 18 mos (3 blocks); 2 yrs (6 blocks); 3 yrs (9 blocks)
– Hops on one foot (age 4)
– Self-grooms and self-dresses (age 4-5)
• Handedness established (by age 6-7)
Summarize the pre-operational (Pre-logical)of Piaget stages
2-7 years
Representations – objects represented by words or images
• Ability to pretend
• Egocentric thought processes predominate
– Difficulty taking other’s perspectives
What is the pre-operational stage?
Pre-operational:
• Basic mental reasoning
• Law of conservation (compensation
abilities) not yet achieved
- Symbolic thinking expands
* The use of symbols or internal images to represent objects, persons, and events (e.g., a child using a stick as a pretend sword)
What are the features of cognitive development in early childhood?
Longer attention span; 5-15 minutes
• Organize objects by size and shape
• Visuospatial Skills (e.g., drawing shapes)
Expansion of language skills (especially from ages 3-5)
– Uses 900 words (age 3) – Sentences
• Sentence Lengths: 3-words (3 years); 4-words (4 years); 5-word (5 yrs) • Uses plurals, pronouns, and compound sentences – Can tell stories and name colors – Asks the meaning of words – 90% intelligible by age 5
Describe emotional development in early childhood
• Struggle for autonomy and separateness from parents (separation/individuation)
• Development of secondary emotions (3 years)
– embarrassment, jealousy, pride, shame, guilt, envy
• Development of basic emotion regulation
– through observing others, talking about
emotion, self-soothing techniques
• Nightmares, fears (e.g., monsters)
What are the social development features of the early childhood?
Gender identity (by age 3)
• Increased interaction (especially from
ages 3-4)
– Understands turn-taking, sharing, and other social rules
– Cooperative play
– Imaginary play and imaginary friends
• Influence of Peers (age 5)
– Social conformity
– Romantic feelings for other
Describe physical development in middle childhood?
• Slow and steady height/weight increase (6 cm/3 kg per year)
– Boys start to weigh more than girls
• Permanent teeth (most by 11 years)
• Refined motor dexterity, speed, coordination
– Ride bicycle
– Write in print and cursive
Describe the cognitive development of middle childhood
PIAGET’s STAGES: Concrete operational stage
(logical thinking) 7-12 years
– Law of conservation: Compensation abilities achieved
– Seriation: Ability to sort stimuli by a characteristic (e.g.,
size)
– Transitivity: Ability to infer relations among elements in a serial order (e.g., If I am taller than Jane, and Jane is taller than Sue, then I am taller than Sue)
• Mental manipulation of objects and processes
• Logical thinking about objects and events but it is still
concrete logic
• Less egocentric and more relational
Summarize cognitive development of middle childhood
Understanding of death (age 8)
• Mnemonic strategies (e.g., rehearsal,
categorization)
• Language
– Shift from egocentric to social speech
– Vocabulary expansion (50,000 words by age 12)
Describe emotional development in middle childhood
• Languagedevelopmentfacilitates:
– Cognitive regulation of emotion (i.e., using
words rather than behavior to express self)
– Behavioral control (through self-talk)
• Internalization of social “display rules” guiding emotion expression (e.g., boys don’t show sadness; girls don’t show anger)
Describe social development in middle childhood
Perspective-taking
– Takes another perspective
– Simultaneously understands multiple perspectives on the same situation
• Understands fairness, generosity
• Competency/competition
– Children start to compare themselves to others
• Organized sport possible
– Focus is on learning “rules of the game”
– Understands value of being a team player
Explain physical development in adolescence
Puberty
– Increase in gonadal hormones
– Second “critical period” in sexual differentiation
– Secondary sex characteristics: breasts, pubic hair, facial hair, larynx enlargement/voice changes
Pubertal growth spurt
– Adolescents attain final 25% of adult height and 50% of adult weight
– Growth spurts earlier in girls than boys
– Different growth rates of body parts (e.g.,
limbs before torso)
– Association between early and delayed growth and behavioral/emotional problems
Sleep rhythms
– The need to sleep is delayed by ~2 hours (“sleep phase delay”)
– 9-hour sleep requirement
– Negative impact of cell phones/computers on sleep hygiene
