Or are they more similar to plants? It is very unlikely jellyfish are conscious due to how simple their nervous system is. It mostly functions to allow rhythmic muscle contraction. There are sensory nervous functions too, namely photosensitivity and gravity sensitivity.

Do jellyfish feel or think?

2. Jellyfish don't have brains. ... And they respond to the changes in their environment around them using signals from a nerve net just below their epidermis - the outer layer of skin - that is sensitive to touch, so they don't need a brain to process complex thoughts.

Does the jellyfish have a brain?

Jellyfish have no brain!

They have a basic set of nerves at the base of their tentacles which can detect touch, temperature, salinity etc. Since they don't have a brain, they depend on automatic reflexes in response to these stimuli!