Understanding the Meaning of 'Prickling'

Read the following excerpt from a novel:

As the tension in the room escalated, Sarah’s heart began to race. She felt a prickling sense of unease creeping up her spine. It was as if the air had thickened with anticipation, rendering her breath shallow. Every word exchanged between the two was laden with unspoken implications, and Sarah couldn’t shake the feeling that the confrontation was inevitable.

In this context, the word prickling most closely suggests: