gist vs mental object

gist and mental object both are nouns.

Word	Noun	Adjective	Verb	Adverb
gist	Yes	No	No	No
mental object	Yes	No	No	No

As nouns, mental object is a hypernym of gist; that is, mental object is a word with a broader meaning than gist:

gist: the choicest or most essential or most vital part of some idea or experience
mental object: the sum or range of what has been perceived, discovered, or learned

Other hypernyms of gist include cognitive content, content.

gist (noun)	mental object (noun)
the choicest or most essential or most vital part of some idea or experience	the sum or range of what has been perceived, discovered, or learned
the central meaning or theme of a speech or literary work