Chapter 4 Physical Development in Infancy
Chapter 4 Physical Development in Infancy
Chapter 4 Physical Development in Infancy
Thirteenth Edition
Chapter 4: Physical Development in Infancy
Changes in Neurons
Neurons – a nerve cells that handles information processing
Myelin sheath – a layer of fat cells, encases axons; provides
energy to neurons
Terminal buttons – release chemicals called neurotransmitters
Continued myelination – process of encasing axons with fat
cells
Greater connectivity and new neural pathways
Shared Sleeping
Varies from culture to culture
Potential benefits:
Promotes breast feeding and a quicker response to crying
Malnutrition in Infancy
Early weaning can cause malnutrition
Two life-threatening conditions resulting from malnutrition
Marasmus: a severe protein-calorie deficiency resulting in a
wasting away of body tissues
Kwashiorkor: a severe protein deficiency that causes the
abdomen and feet to swell with water
Severe and lengthy malnutrition is detrimental to physical,
cognitive, and social development
Sucking Reflex
Moro Reflex
Grasping Reflex
Learning to Walk
Occurs about the time of their first birthday
Infants learn what kinds of places and surfaces are safe for
locomotion
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Gross Motor Skills: large-muscle activities
The First Year: Motor Development Milestones and Variations
Some milestones vary by as much as two to four months
Depth Perception
Eleanor Gibson and Richard Walk studied development of
depth perception using a “visual cliff”
Hearing
Fetuses can hear and learn sounds during the last two months
of pregnancy and can recognize their mother’s voice at birth
Smell
Newborns can differentiate odors
Taste
Sensitivity to taste may be present before birth