The thorn necklace could allude to the idea of martyrdom, and here Kahlo becomes the martyr wearing it. This also alludes to the religious narrative that relates to the crucifixion of Jesus Christ and when He wore the crown of thorns.
In the Self-Portrait with Thorn Necklace and Hummingbird by Frida Kahlo, she is facing us in a full-frontal stance just exposing her upper torso, neck, and head. She is wearing a white blouse and her hair is held up.
Kahlo conveyed texture in different ways; for example, she utilized smoother brushstrokes for her skin and more varied, shorter brushstrokes to indicate the hair (fur and feathers) for the monkey, cat, and bird.