Final answer:
The bank teller's distraction due to the weapon in a robbery scenario is an example of 'Weapon focus', a psychological phenomenon affecting eyewitness memory.
Step-by-step explanation:
The scenario described, where a bank teller fails to notice the features of a criminal because she is focused on the weapon, is best illustrated by the term Weapon focus. Weapon focus is a phenomenon observed in eyewitness testimony in which the presence of a weapon draws attention and impairs a witness's ability to remember other details of the crime scene.
Weapon focus refers to the phenomenon where a person's attention is primarily directed towards a weapon during a threatening situation, leading to a reduced ability to accurately perceive other details. This can occur due to the emotional impact of the weapon, which can capture and dominate a person's attention.
This is not to be confused with Retroactive interference, which occurs when newer information interferes with the retrieval of older information, or Source amnesia, which involves forgetting the origin of a memory while retaining its content, or Flashbulb memory, which is a highly detailed and vivid memory of an emotionally significant event.