Final answer:
The indication for hearing loss assessment in an 18 month old toddler is the lack of response to loud noises. Hearing is well developed at birth, and preferences for the mother's voice are established prenatally. Non-responsiveness to auditory stimuli at this age may suggest hearing impairment and warrants further evaluation.
Step-by-step explanation:
Hearing Loss Indicators in Toddlers
Among the options provided, the finding that would indicate a need to assess an 18 month old toddler for hearing loss is option 4: The toddler does not respond to loud noises. Toddlers are expected to have a well-developed sense of hearing and typically show responses to noises in their environment. By 18 months, toddlers should be able to recognize sounds and respond to verbal commands; they can generally say a few words, such as "mama" and "dada," and are able to follow simple directions. Additionally, they are gaining independence in movement, such as walking. The ability to stack blocks is a motor skill and does not relate directly to hearing.
It's also essential to address parental concerns about auditory development during prenatal care. Infants already have a developed sense of hearing at birth. This includes a preference for their mother's voice, as it is a familiar sound heard while in the womb. Studies have shown that newborns can distinguish their mother's voice, and this preferential recognition can have a soothing effect on the infant.
If a toddler does not respond to loud noises, it may suggest potential hearing loss, which requires further assessment by a healthcare professional, as early detection and intervention can be critical for language development and overall well-being.