In a newborn experiencing kernicterus, which of the following symptoms would be observed?

Kernicterus is a serious condition that occurs when there is an accumulation of bilirubin in the brain due to untreated jaundice, leading to neurological damage. In newborns with kernicterus, one of the predominant symptoms is hypotonicity, which refers to reduced muscle tone. This can manifest as a decreased response to stimuli and weakness in the limbs, making the infant appear floppy or less active than usual.

Hypotonicity occurs as a result of the direct effects of high bilirubin levels on the central nervous system, impacting the muscles' ability to maintain tone. Newborns typically exhibit varying degrees of muscle tone, and hypotonia is often a significant and concerning finding in those with bilirubin encephalopathy.

While jaundice is an accompanying symptom of elevated bilirubin levels, it is not specific to kernicterus and is not a direct neurological symptom. Hyperactivity is also not associated with kernicterus; rather, newborns usually exhibit lethargy in these cases. Normal feeding behavior is not typical either, as infants might struggle with feeding due to their overall decreased responsiveness and energy levels as a result of the condition.