If you're referring to (1970) — which argued that neurosis stems from repressed birth/childhood trauma and that re-experiencing it through a "primal scream" is therapeutic — and the PDF is a modern take on it, here is a generic post you could adapt:
Drawing on Dr. Bessel van der Kolk’s The Body Keeps the Score , this section updates Janov for the fMRI era. It explains that the primal scream isn't just psychological—it is physiological. details how unexpressed trauma lowers the vagal tone, keeping the sympathetic nervous system (fight/flight) permanently activated. The "scream" is presented as a mechanical reset: a forced exhalation that stimulates the vagus nerve, lowering cortisol levels by up to 40% in clinical trials cited within the text. The New Primal Scream.pdf