How fragile is short-term memory without active rehearsal, based on experimental findings?

Short-term memory is considered to be very fragile without active rehearsal, which aligns with the findings from various psychological experiments. Research has shown that without ongoing mental activity to maintain the information, short-term memory traces begin to decay rapidly. Typically, information held in short-term memory can only be retained for about 15 to 30 seconds without active rehearsal, such as repetition or cognitive manipulation, before it is forgotten.

This fragility is demonstrated in classic experiments, such as those involving the serial position effect, where items presented in a sequence can be recalled better if they are prominently rehearsed. The lack of rehearsal means there is little to no active cognitive maintenance of the information, leading to a high rate of forgetting. This aspect of short-term memory highlights its limited duration and vulnerability to interference, which underscores the importance of rehearsal strategies for retaining information over even short periods.