The human soul has sojourned in lower and higher forms, migrating from one to another according to the samskaras or impressions, but it is only in the highest form as a human being that it attains to freedom.
Genuine religion is not about speculating about God or the soul or about what happened in the past or will happen in the future; it cares only about one thing finding out exactly what should or should not be done in this lifetime.
The seat of the soul and the control of voluntary movement - in fact, of nervous functions in general, - are to be sought in the heart. The brain is an organ of minor importance.