What refers to automatic muscle reactions in infants that disappear as they grow?

The term that refers to automatic muscle reactions in infants, which typically diminish as they grow older, is recognized as infant reflexes. These reflexes are innate behaviors that infants display in response to specific stimuli and include well-known examples such as grasping, rooting, and the Moro reflex. These reflexes are crucial for survival and development in the early stages of life; for instance, the rooting reflex helps infants find the breast for feeding.

As infants develop, their nervous systems mature, and these automatic reflexes gradually fade as they are replaced by voluntary movements and more complex motor skills. The process signifies developmental milestones as infants gain greater control over their movements through learning and practice.

In contrast, conditioned reflexes involve learned responses through repeated pairings of stimuli, which do not apply to the innate reflexes present at birth. Motor skills refer to the controlled movements that develop over time and require practice and coordination, while instinctual responses apply broadly to behavior across species and cannot be specifically tied to the reflex actions observed in human infants. Thus, the reference to automatic muscle reactions that disappear with growth accurately aligns with the concept of infant reflexes.