Infant Development I_FA24
Infant Development I: Physical, Sensory, Perceptual (NURS-201)
Objectives
Brain changes during infancy
Predictable changes in reflexes and states as indicators of nervous system health
Typical pattern of motor skill development in the first 2 years
Factors influencing motor skill development
Changes in body systems during infancy
Infants' sensory abilities: hearing, vision, taste, and smell
Infants’ perceptual development: depth, perception of patterns, intermodal perception, and listening
Nutritional needs of infants
Types of malnutrition during infancy
Risk factors for SIDS (Sudden Infant Death Syndrome)
Differences in infant mortality across groups
Vaccination needs during the infancy stage
What is the Infant Period
Neonate/Newborn Period: 0-28 days of life (first month)
Infancy Period: 28 days – 12 months (1 month – 1 year)
Physical Changes
Physical Growth & Reflexes
Behavioral States Development
Motor Skills Development
Body Systems Growth
Physical Growth & Development Overview
Greatest physical development occurs during infancy
Height: Grow 10-12 inches in 1st year
Weight:
Infants double their birth weight at 6 months
Infants triple their birth weight at 1 year
Example: Sally weighed 6 pounds at birth, so she will weigh:
12 pounds at 6 months
18 pounds at 1 year
Variations in growth can be due to genetics, nutrition, or illness.
Head Circumference
Suture lines and fontanels remain unsealed at birth to allow brain growth
Posterior Fontanel: Closes by 3 months
Anterior Fontanel: Closes between 12-18 months
Measuring head circumference monitors overall growth and potential complications
Brain weight triples by age 2, influencing infant's top heaviness.
Brain Physical Growth
Midbrain & Medulla: Fully developed at birth, controlling vital functions
Cortex: Responsible for perception, thinking, language, and movement; minimal development at birth
Cerebellum: Controls coordination and balance; develops skills such as crawling and walking during infancy
Nervous System Growth
Composed of neurons and glial cells
Synapses: Connections allowing signal processing
Synaptogenesis: Creation of synapses occurring in clusters, a key developmental process
Pruning: Elimination of excess synapses enhances brain efficiency
Brain and Nervous System Growth
Plasticity: Ability to change in response to experiences; important for brain growth
Myelinization: Formation of axon sheaths that improves neuron communication
Infant Reflexes
Adaptive Reflexes: Promote survival; presence indicates proper brain function
Primitive Reflexes: Disappear by 6-8 months; persistence may indicate neurological issues
Normal Infant Reflexes
Babinski Reflex: Toes fan out when bottom of foot stroked
Moro Reflex: Startle response with loud noises or sudden movements
Rooting/Sucking Reflex: Infants turn mouth towards stimulus
Palmar Grasp Reflex: Fingers close around objects placed in their palm
Stepping Reflex: Mimicking walking when feet contact a flat surface
Infant Behavioral States (States of Arousal)
Deep sleep: Brain recovery
Light sleep: Active REM sleep for development
Drowsiness: Sleepy lower energy state
Quiet alert: Engaged without fussiness
Active alert: Signs of discomfort or fussiness
Crying: Distress state, difficult to calm.
Bone & Muscle Physical Growth
Growth follows Cephalocaudal and Proximodistal patterns
Bone Growth: Mainly cartilage at birth, ossification occurs during infancy
Muscle Growth: Muscle fiber composition changes to increase strength
Gross vs. Fine Motor Development
Gross Motor: Large body movements - males usually faster
Fine Motor: Small precise movements - females usually faster
Gross Motor Development Milestones
1 month: Stepping reflex, head lifting with no control
2-3 months: Head control gained
4-6 months: Rolls over and sits with support
10-12 months: Pulls up and walks with support
Fine Motor Development Milestones
1 month: Grasping object
2-3 months: Swipes objects
9 months: Develops pincer grasp
10-12 months: Hand preference begins
Sensory Development
Vision: Poor acuity at birth; rapid improvement within the first year
Hearing: Better at birth compared to vision; recognizing mother's voice by 1 month
Taste: Can distinguish basic tastes at birth; preference for sweet and umami
Smell: Recognize mother's scent; olfactory system develops early
Perceptual Skills
Depth Perception: Ability to judge distance and depth develops over 6 months
Perception of Patterns: Preference for contrasts and motion
Intermodal Perception: Integrating information across senses
Ways to Encourage Perceptual Development
Parental Interaction: Engage through talking, singing, reading
Model Speech: Emphasize good communication and opportunities for interaction
Infant Mortality
Definition: Death of an infant within the first year; US rate at 5.4/1000 live births
Directly linked to congenital anomalies and low-birth weight
Differences by Ethnicity: African American infants have higher rates
Sudden Infant Death Syndrome (SIDS)
Leading cause of death in infants 1 month to 1 year old
Prevention: Safe sleeping practices; education on potential causative factors
Shaken Baby Syndrome
Definition: Neurological issues from forceful shaking
Education Needed: Understanding newborn behavior and calming techniques
Infant Nutritional Needs
Feeding: Formula or breast milk for the first year; solids from 4-6 months
Breastfeeding Advantages: Immunologic benefits, convenience; disadvantages include time commitment
Formula Feeding: Designed to resemble breast milk; possible issues with overfeeding
Malnutrition**
Macronutrient Deficiency: Too few calories; leading cause of death in under 5s
Micronutrient Deficiency: Impairs brain and growth development
Kwashiorkor: Protein deficiency; Marasmus: Severe nutrient deficiency leading to serious growth issues
Health Maintenance**
Encourage routine check-ups and immunizations
Promote physical exams to identify issues
Infant Immunizations**
Schedule of vaccinations outlined from birth to 6 years
Dr. Hip mnemonics to remember vaccination types and timing.