Kahlu speaks: Thanks for your question. Convergence is mostly mediated from the central nervous system, although there are probably ANS components. So when looking through base out prism, the brain’s centering center is activated. For the human aspect, they are asked: “How much can you stay centered within yourself without becoming disintegrated?” In Psychological terms, this means not becoming disassociated. Looking through Base out prism is a direct way of examining how well the person can move into the core centre of him or herself. How does this help? To center inwards is to enter a self-exploration of knowing one’s real self through observation. Hence my quote, with the mentoring of Ricardo Rojas!

“You can never know self! Self is the process of observing!”

We know from MRI and fMRI studies that those who meditate, and are emotionally calm inside themselves, have faster convergent and divergent abilities as measured with computer generated images.
Looking through Base in Prism directs the brain’s response to diverge. Mechanically this can be quantified in prism diopters, however, the evaluation on the human level asks how divergent can this person be in their view without entering duality, maybe even into a split personality, or some other form of mental perceptual distortion. To be divergent is to be flexible and non-rigid. Divergent perceptual abilities grant one the possibility to engage in conversations with less ego attachments, thus seeing many points of view.
Of course, the binocular view of life can be affected by the autonomic nervous system under emergency situations, but training with prisms is a much deeper and more far reaching process because of the direct access to the human mind via the CNS.
Combining prism Base out with minus lenses activates both nervous systems and thus explains why vision therapy is such a deeply effective process touching the very core of the human being. Thanks you, Kahlu.