Are there organs or cells associated with particular emotions?
I was thinking about how: in the eyes, there are cones of three kinds (one for each of the primary colors) along with rods; on the tongue there are five, give or take, kinds of buds; on the skin there are multiple kinds of "sensor", including for pressure and for temperature, maybe for humidity.
To my knowledge, the distinct regions of the cerebral cortex process distinct physical stimuli, but when it comes to the metal phenomena termed "emotions", the way they correspond to regions of the cerebral cortex becomes jaded or at least work in a Venn diagram kind of mutual non-exclusion.
I think, if we could identify a finite set of things in the cerebral cortex, then we might be able to determine how many "primary" emotions exist and how to precisely define them and composite forms of these things. All we have to go by is "body language", pupil dilation, heart rate and blood pressure, among other things, to which meaning is assigned to the various kinds of expressions or behaviors cross-referenced with what to the best of his/her ability the subject or specimen informs as to his/her "thoughts" and "feelings".