Population-wide error bar plots: CPP versus PRx, CPP versus PAx, and CPP versus RAC. AMP, pulse amplitude of ICP; a.u., arbitrary unit; CPP, cerebral perfusion pressure; ICP, intracranial pressure; PAx, pulse amplitude index (correlation between AMP and MAP); PRx, pressure reactivity index (correlation between ICP and MAP); RAC, correlation between AMP and CPP. Note: Vertical dashed line represents the approximate mean LLA for the population, derived through piece-wise linear regression in each animal.