Which reflex is primarily tested when evaluating spinal cord function in newborns?

The anal wink reflex is primarily tested when evaluating spinal cord function in newborns because it provides direct insight into the integrity of the spinal cord and its related pathways. This reflex involves the contraction of the anal sphincter when the perianal area is stimulated, indicating that the sacral segments of the spinal cord are functioning appropriately.

When assessing neurological function in newborns, specifically regarding spinal cord integrity, the anal wink reflex is crucial because it demonstrates functional activity within the lower spinal regions. It can help identify potential abnormalities or neurologic issues, allowing for appropriate clinical decisions to be made. In contrast, the other reflexes such as the rooting reflex, grasp reflex, and Moro reflex, while important for assessing general neurological health and development, primarily reflect brainstem and higher brain functions rather than specific spinal cord activity.