The article discusses the negativity bias in social-emotional development, arguing that infants and children exhibit a tendency to attend more to negative information than positive. This bias is proposed to have evolutionary and developmental functions, influencing how infants process and respond to emotional cues. The study reviews evidence from social referencing, where infants use caregivers' emotional cues to interpret ambiguous situations. Research shows that infants react more strongly to negative cues, such as fear or disgust, than positive ones, suggesting a negativity bias in social referencing by the end of the first year. This bias is supported by neuroscientific evidence, including event-related potentials (ERPs) showing greater neural processing of negative stimuli. The article also explores the negativity bias in other developmental domains, such as discourse and memory, where children use more negative words and recall negative events more vividly. The emergence of the negativity bias is discussed in terms of ontogenetic mechanisms, including attention to emotional expressions and emotional contagion. While some studies suggest a negativity bias in infants, others show no significant difference, highlighting the need for further research. The article concludes that the negativity bias is a significant aspect of early development, influencing emotional and social-cognitive growth.The article discusses the negativity bias in social-emotional development, arguing that infants and children exhibit a tendency to attend more to negative information than positive. This bias is proposed to have evolutionary and developmental functions, influencing how infants process and respond to emotional cues. The study reviews evidence from social referencing, where infants use caregivers' emotional cues to interpret ambiguous situations. Research shows that infants react more strongly to negative cues, such as fear or disgust, than positive ones, suggesting a negativity bias in social referencing by the end of the first year. This bias is supported by neuroscientific evidence, including event-related potentials (ERPs) showing greater neural processing of negative stimuli. The article also explores the negativity bias in other developmental domains, such as discourse and memory, where children use more negative words and recall negative events more vividly. The emergence of the negativity bias is discussed in terms of ontogenetic mechanisms, including attention to emotional expressions and emotional contagion. While some studies suggest a negativity bias in infants, others show no significant difference, highlighting the need for further research. The article concludes that the negativity bias is a significant aspect of early development, influencing emotional and social-cognitive growth.