Further to your query, I believe you are correct. The suttas speak of a physical support for the mind, but the Buddha does not specify precisely where that is.
It seems to be only in the commentaries that the physical location comes to be attributed to the heart, as was one of the prevailing beliefs at the time in India.
[Which neither makes it inherently right or wrong - only that in this particular sub-forum, that is sufficiently authoritative in itself]
"Do not force others, including children, by any means whatsoever, to adopt your views, whether by authority, threat, money, propaganda, or even education." - Ven. Thich Nhat Hanh
"The uprooting of identity is seen by the noble ones as pleasurable; but this contradicts what the whole world sees." (Snp 3.12)
"To argue with a person who has renounced the use of reason is like administering medicine to the dead" - Thomas Paine