What is Infant Mental Health?

Written by Dr. Alicia Pointer | Feb 26, 2026 12:30:00 PM

When we think about mental health in kids, a lot of times we think about depression and anxiety in older children and teens. But children’s mental health journey starts the moment they’re born. What happens to babies when they’re very young can affect their long-term development, behavior, and social-emotional outcomes. Recognizing how infants express their emotions and what they need to support their mental health has the potential for lasting positive impact.

Zero to Three defines Infant and Early Childhood Mental Health “developing the capacity of the infant and young child to form close and secure relationships; to experience, manage, and express a full range of emotions; and explore the environment and learn—all in the context of family, community, and culture.”

Infants have relationships.

From the moment they’re born (and probably even earlier), babies are forming bonds and connections. Studies show that newborns already recognize and prefer their mother’s voice. And we know that early skin to skin contact with a parent not only helps with newborns’ stress and crying but also improves their breathing, heart rate, and blood sugars.

Infants are soothed by the voice and touch of adults close to them. They make their first smiles, laughs, and words in response to the people around them. Babies’ brains are built for connection.

Imagine a baby becomes startled by a loud noise and starts to cry. A familiar adult picks them up, makes gentle “shushing” sounds, and rocks them back and forth. The baby stops crying, relaxes their body, and calms their breathing. This is a building block of emotional regulation, a key component of mental health.

As babies progress through infancy and toddlerhood, these early relationships continue to shape their brain development, sense of safety, emotional regulation, and social skills. Safe, stable, and nurturing relationships are one of the most important ways to promote resilience and buffer against the harms of toxic stress.

Infants have emotions.

Babies don’t tell us that they feel anxious or depressed. But it’s no surprise that babies have moods and feelings. We can tell when a baby is calm, agitated, upset, content, scared, or excited. Parents with more than one child will often notice differences in their children’s temperaments (or personality) even as newborns.

Even before they understand what adults are saying, infants pick up on caregivers’ facial expressions and tone of voice. When a baby smiles and coos at their parent, does their parent smile and talk back? When a toddler throws a toy in frustration, does their parent respond with anger or patience?

From the time they’re born, babies are learning about their own emotions and figuring out how they and others respond to those emotions. Caregivers support infants’ mental health by tuning in to their cues and recognizing their feelings.

Understanding and reacting to feelings are key components of mental health.

Infants respond to their environment.

Babies are affected by what’s around them. Their brains learn and grow as they explore their environment. Even at a very young age, stressful environments can impact on infants’ health. In the NICU, loud sounds, bright lights, and frequent procedures can all negatively affect preterm newborns’ vital signs. Responding to one’s surroundings and adjusting to new situations is a key component of mental health.

Infants also learn from adult responses to what’s around them. When babies see something new or potentially scary, they’ll often look to their parent to see what their response is. If the parent is available and reassuring, the baby is less likely to show signs of stress or fear.

A baby’s environment can have positive impacts on them, too. Spending time outdoors or in nature helps decrease stress and boosts concentration. Free play with simple toys teaches problem-solving. Consistent routines and cultural traditions strengthen resilience and a sense of security.

Safe and healthy surroundings, stable routines, and opportunities for play and exploration promote infants’ social, emotional, and cognitive health.

 

Resources

AAP: Promoting Safe, Secure, and Nurturing Relationships

New York State Association for Infant Mental Health

Pathways: Social and Emotional Development

Zero to Three