But as he stood there, looking across the street at two men coming out of the Red Apple with a six-pack apiece, he suddenly did know something, remembered something that drew a cold line up his back. <…> His nerves suggested strongly that it did –the cold line up his back had both widened and deepened. Source: Insomnia by Stephen King Did the character actually feel a cold line up his back or is it a metaphor? would it be correct to gloss that bolded clause is almost equivalent to ‘his spine shivered’? Thank you.