What does this equation mean?

The reframing also fits what clinical treatment for phobia actually looks like, without needing an additional assumption. Exposure-based treatment works by driving V back down toward zero through repeated, non-reinforced exposure to the feared stimulus — a description that says nothing about $\alpha$ at all. If preparedness operates on the learning rate for acquisition rather than on some separate, treatment-resistant substrate, there is no particular reason a prepared association should be harder to unlearn once a patient is actually engaged in structured extinction; it need only have been easier to learn in the first place and, per McNally’s reading of the acquisition-side evidence, easier to tell apart from irrelevant stimuli during that learning [ 13 ] . A dedicated, encapsulated module framed as impenetrable to cognitive control would predict something closer to a treatment-resistance specific to prepared categories, over and above ordinary extinction difficulty; nothing in the evidence reviewed here establishes that such a category-specific treatment resistance exists, which is itself a reason to prefer the more modest, single-mechanism account over the stronger one.