What is the neurophysiology of a thought?
Hence, my question: Is there any scientific evidence that support that the cell assembly is the basis of thought/a concept?

This paper Thinking in circuits reviews this matter in detail, and its references can provide more related scientific evidence.

Question: What is the neurophysiology of a thought?

I think the following papers can provide some current information about the neurophysiology of thought:

1.How neurons make meaning

2.Brain Networks and Cognitive Architectures

3.Language and thought are not the same thing