By what age should infants show parallel eye movement without deviation?

Infants typically develop the ability to track objects with their eyes in a coordinated manner by around 6 months of age. At this stage, they should exhibit parallel eye movements, meaning that both eyes move together in the same direction without any noticeable deviation. This development is essential for visual tracking and plays a crucial role in an infant's overall sensory and cognitive development.

At 2 weeks, infants have limited control over their eye movements, and they often show random or uncoordinated eye movements. By 3 months, while there's improvement in visual tracking, it may not yet be fully refined, and deviations might still occur. By 1 year, most infants have developed more advanced eye coordination and tracking skills, but the specific milestone for achieving consistent parallel eye movements is generally recognized to be around 6 months of age. This is why indicating 6 months as the correct answer reflects an understanding of normal developmental milestones in infant eye movement coordination.