His head jerked up at the sound of running feet above them.

Joe's head jerked up, and all the color washed out of his face.

Every head in the office jerked up at her, startled.

Seven's head jerked up at the name of the system.

He was about to say something to that effect when Benjamin's head jerked up suddenly.

Her head jerked up, and she met his eyes at last.

The boy's head jerked up at the sound of his name.

His head jerked up to look at me, eyes clear and hard.

She bent to study it and then her head jerked up.

Then the head jerked up again with wide open jaws.