Having trouble wrapping my mind around the idea of using transcriptomics or proteomics to classify "cell types". We know that experience can change gene expression in neurons ... so does this mean that experience changes your cell types? I feel like the traditional idea is that some internal program specifies cell type, which changes function, which drives behavior, with causality going in one direction. But if interaction with the world can change cell type, then causality is going both ways, and the notion of a cell type no longer seems that useful to me.
Maybe one idea (which I heard during Gord Fishell's seminar recently) is to distinguish between cell types (irreversible developmental changes) and cell states (reversible changes of function).
@chrisXrodgers I totally agree with you. But the problem is that many of the "cell type" markers are activity regulated. So then how would one define "cell type" without considering "cell state"? I think a more holistic way of categorizing cell types is needed, for example there is some recent examples of utilizing morphology and electrophysiological properties in addition to transcriptomics for categorizing neuronal types (i.e. MET-types).
