Gabriel is a normal 4-month-old infant. Thus, we would expect him to have:

At 4 months of age, infants typically exhibit implicit memory, which refers to the type of memory that involves learning information without conscious awareness. This form of memory is foundational for tasks such as recognizing familiar faces, remembering routines, and engaging with objects and people in their environment. Implicit memory develops earlier than explicit memory, which becomes more prominent as children grow older, typically starting to develop around the age of 2 or 3.

The characteristics of implicit memory in infants include their ability to show recognition or preference for previously encountered stimuli without having explicit recall of those experiences. It is a key component of their cognitive development and allows them to learn about their surroundings effectively.

In contrast, explicit memory involves conscious recollection of information or experiences and is not typically present in infants younger than 2 years. Therefore, at 4 months, Gabriel would not have developed explicit memory.

The idea of no memory retention does not accurately reflect the capabilities of a 4-month-old, as they do have some memory through implicit processes. Similarly, the notion of enhanced long-term memory is not applicable for infants at this developmental stage, as their memory capabilities are still in early formation and primarily revolve around implicit memory mechanisms.