Now I feel like a burger. Just writing this produced a neuro-chemical reaction that made my mouth water. 🍔
We are talking here about those hard-wired emotions which are related to survival.
Electrical impulses from our sensory organs initiate the neuro-chemical reactions which produce those feelings and responses. (The sensory organs are all just what in electrical terms are called "transducers" - with a transducer being a device which converts any other form of energy into electrical energy).
Additionally, memories (pleasant or otherwise) which are stored in the brain can likewise initiate the electrical signals which stimulate those neuro-chemical reactions. There is no black magic involved here; all these processes can be observed to occur by use of such devices as MRI scans (and the electrical signals between the neuron cells can be measured).
Such concepts as "God" came about primarily because of the insatiable curiosity of the human species, and its early attempts to explain what was going on around it. (And in stating that, I have likely condemned myself in the eyes of many posters on this thread, but whatever!)