A Topical Approach to Life-Span Development 6e John W. Santrock Chapter 3: Physical Development and Biological Aging

Patterns of body growth Cephalocaudal pattern = Proximodistal pattern = Growth rate affected by :

Figure 3.1 - Changes in Proportions of the Human Body During Growth Fractions = head size as fraction of total body length

Height and Weight in Infancy and Childhood Average ___ inches, ____ lbs at birth Triple weight by ___ year By age ___, reach ½ adult height, 1/5 adult weight Early Childhood Growth _____, trunk __________, body fat __________; patterns vary individually Girls slightly _________ and __________ than boys Girls have more ______ tissue, boys more __________ Middle and Late Childhood Slower, consistent growth Muscle mass and strength _________; bones _______ Body proportions change; boys stronger

Puberty: Physical growth & change Growth spurt Order for girls: Age of onset: Order for boys:

Puberty: Hormonal Changes Hormones =

Endocrine glands & functions Hypothalamus – Pituitary gland – Gonads = Gonadotropins =

Endocrine glands  pubertal changes

Puberty: Hormonal effects Hormones increase dramatically Testosterone  Estradiol  Puberty onset affects social competence Behaviors and moods can affect hormones

Timing of puberty: Psychological effects Early maturation Boys: Girls: Late maturation http://digital.films.com/PortalPlaylists.aspx?aid=13174&xtid=47960

Physical Changes: Early adulthood Height Muscle tone, strength Joint functions Elasticity

Middle adulthood: Physical Changes 40s-50s Declines: Increases:

Middle adulthood: Body Changes Strength, joints, and bones

Middle adulthood: Body Changes Cardiovascular system Lungs

Middle adulthood: Sexuality changes Climacteric — Menopause —

Physical Changes: Late adulthood Physical appearance Circulatory system

Figure 3.6 - The Brain’s Four Lobes Frontal Attention, thinking, personality, intentionality or purpose Motor cortex: voluntary movement Occipital Visual cortex Parietal Somatosensory cortex: Processing body sensations (sense of touch); spatial location Link to motor cortex – body & movement control Role in attention Temporal Auditory cortex: hearing Language processing, memory

Functions of Cortical Lobes Frontal Motor cortex: Parietal Somatosensory cortex: Occipital Visual cortex: Temporal Auditory cortex:

Brain Physiology: Neurons Neurons: Nerve cells that…

Figure 3.7 - The Neuron

Neuron Structures & Functions Dendrites, cell body, axon Myelin sheath and myelination Neurotransmitters Synapse

Neural circuits = groups of specialized neurons

Neural Growth in Infancy Born with about __________ neurons Rapid growth of:

Figure 3.12 - Dendritic Spreading

The Brain in Infancy Skills affected by: Blooming & pruning of: Brain areas do not mature uniformly Rapid growth of: Motor control begins at about:

Figure 3.13 - Synaptic Density in Human Brain from Infancy to Adulthood

The Brain in Childhood Brain and head continue to grow more rapidly than any other part of the body (See Fig. 3.13) Greatest anatomical brain increases from ages:

Figure 3.14 - Growth Curves for Head and Brain and for Height and Weight

The Brain in Childhood Age 3 – 6: most rapid growth in: Age 6 – puberty: most growth in:

The Brain in Adolescence Growth in: Corpus callosum – Amygdala – Prefrontal cortex –

The Brain in Adulthood General slowing of which functions? Begins in middle age, accelerates with age Brain loses _____% of weight from age 20 - 90 Shrinkage is not uniform; most in:

The Brain Can Adapt! How can we maintain functions & slow decline? Remarkable repair capability Neurogenesis: