PTH and concussion: Furthermore, previous mTBI, being injured while abusing alcohol, and acute HAIH were described as persistent HAIH predictors; the disrupted periaqueductal gray-default mode network (PAG-DMN) connectivity predicted PTH outcomes of mTBI individuals 12 weeks after injury; female sex, neck pain, two-week post-mTBI symptoms, and two-week post-traumatic stress were significant PPCS predictors (see Table 2).