Analysis of Nonlinear Structure in Plot Development

Read the following excerpt from a fictional novel:

The streets were eerily quiet as Julian made his way home, the usual cacophony of laughter and music completely absent. Shadows danced under the dim streetlights, exaggerating shapes that seemed to loom larger than life. Suddenly, a distant sound—a chilling scream—snapped the silence, sending shivers down his spine. The hairs on his neck stood on end, and an invisible weight pressed upon him as memories of that fateful night flooded back. It was a night he had tried desperately to forget, a night that had altered the course of his life forever.

In this novel, the author employs a nonlinear structure, alternating between Julian's harrowing memories and the present moment. This technique serves to build suspense and deepen the reader's understanding of Julian's psyche as he grapples with trauma.

Which structural element primarily enhances the development of the plot in this excerpt?