Which reflex should a 6-month-old infant exhibit during assessment?

At 6 months of age, the plantar grasp reflex is expected to be present. This reflex is characterized by the infant's toes curling or grasping when the sole of the foot is stroked. This reflex typically emerges in newborns and can persist until about 9 to 12 months of age, serving as an indicator of neurological function and development.

In contrast, the Moro reflex, which involves a startle response where the infant throws their arms outward and then brings them back in, is generally present from birth and starts to diminish around 3-6 months. The stepping reflex, where the infant appears to take steps when held upright with their feet touching a flat surface, is often seen from about 6 weeks to 2 months but gradually fades as the child learns to control their movements. The tonic neck reflex, which causes a newborn to turn their head to one side and extend the corresponding arm and leg, is present from birth and usually disappears by 4-6 months.

Hence, at 6 months, the plantar grasp reflex is the most fitting reflex that should be assessed.