This chapter will focus on the rapid and amazing development that happens during infancy and toddlerhood. The first 3 years of life are marked by intense growth and skill-building. Children are hardwired to learn, beginning in the womb and expanding after birth. During this developmental period, their brains experience one million neural connections per second (Zero to Three, 2023). This is an amazing feat!

Children work through several important cognitive, language, and physical milestones during these 3 years. While newborns may appear passive in their early interactions, they are born with the instinct to gather and process information from their caregivers and environments. We start to see this blossoming during infancy and toddlerhood, when the child begins to demonstrate their knowledge through communication and movement.

Primary caregivers are of utmost importance during this developmental period. They not only care for the basic needs of their child, but also work to enrich their child’s lives through connection and play. Children also need access to healthy environments and communities that provide opportunities for education, healthcare, and positive social interactions.

We will explore the expanding brain and body and discuss the factors that support growth. We will also look at the diverse cultural approaches to caring for infants and toddlers. There is no “right” way to raise children, but we can agree that all children deserve healthy caregivers, nurturing interactions, and enriching opportunities.

Learning Objectives

After reading this chapter, you will be able to do the following:

1. Identify the stages of infant and toddler cognitive and physical development.
2. Identify communication milestones in infancy and toddlerhood.
3. Recognize healthy sexual development in infancy and toddlerhood.
4. Analyze the impact of caregivers, social context, and cultural influences on a child’s development.

Key Terms

Throughout this chapter, you will be introduced to important key terms that will help deepen your understanding of human development.

• Accommodation: a cognitive process that occurs when an existing schema is updated or a new schema is created
• Animism: the belief that inanimate objects have lifelike abilities
• Assimilation: a cognitive process that occurs when a current schema is applied to understand something new
• Child-directed speech: a type of speech characterized by slower delivery of words, higher tones, and pronounced facial expressions
• Egocentrism: the inability to see the world through other people’s perspective.
• Experience-dependent plasticity: the remodeling of the brain due to unique or unexpected experiences within and outside sensitive periods of development
• Experience-expectant plasticity: the guidance of normal brain development by environmental stimuli, especially during sensitive periods
• Fine motor skills: motor development that focuses on the muscles in our fingers, toes, and eyes, which enable coordination of small actions
• Gross motor skills: motor development that focuses on the large muscle groups that control our head, torso, arms and legs, which enable the coordination of larger body movements
• Holophrastic speech: young children’s use of one-word phrases or expressions to convey thoughts
• Magical thinking: children’s belief that their thoughts or actions influence things that happen in their environment
• Mental representations: the ability to think about things that are not currently present or to think about something in the past
• Neurons: a type of brain cell that sends signals to the nervous system
• Neuroplasticity: a process that involves adaptive structural and functional changes to the brain
• Object permanence: the understanding that even though something is out of their sight, it still exists
• Overextension: the application of a label to all objects that are similar to the original object
• Palmer grasp: the ability to grasp an object using the fingers and palm without the thumb
• Pincer grasp: the ability to grasp an object using the forefinger and thumb
• Preoperational stage: the second stage of Piaget’s theory of cognitive development during which children learn through symbolic and intuitive thought
• Receptive language: children’s ability to understand language before they produce speech
• Schemas: categories of knowledge within the brain that help make sense of and process information
• Sensitive periods of development: periods when brain connections reach their peak for certain functions and skills
• Sensorimotor stage: the first stage of Piaget’s theory of cognitive development, during which children develop an understanding of the world through their senses
• Symbolic function substage: a substage of preoperational development that is characterized by gains in symbolic thinking, which allows for advances in language development, problem solving, and memory
• Synapses: connections between neurons that help relay information
• Synaptic pruning: the process by which the brain eliminates certain neural connections and strengthens others
• Telegraphic speech: a practice in which children leave out unnecessary words and use two to three word phrases to communicate
• Toxic stress: stress that results in excessive or prolonged activation of stress response systems in the body and brain
• Tummy time: the practice of placing an infant on a flat surface on their stomachs during awake times
• Underextension: the application of a word to a specific object but not to others that are similar
• Zone of proximal development: the period when a child is close to performing a task independently but needs assistance to complete it

Licenses and Attributions for Chapter Overview and Learning Objectives

“Chapter Overview” by Christina Belli is licensed under CC BY 4.0.