Identifying Flashback

In the following excerpt from a novel, a character reflects on a significant event from their past:

"As she walked through the familiar streets, memories flooded back to her. It was just a year ago when she stood by the old oak tree, feeling the weight of her decision as she watched her father walk away, never to return. The laughter of children playing nearby reminded her of the summer days spent in that very spot, where she had made that fateful promise to herself to never let go of her dreams."

Which of the following literary devices is primarily employed through the phrase 'As she walked through the familiar streets, memories flooded back to her'?