PhronesisWe apply the Displacement Framework to Acquired Brain Injury (ABI), identifying it as formally unique among conditions in this series: not a wrong attractor capture but potential ground state erasure. The pre-injury person had a neurological ground state S°_pre — a coupled configuration of cognitive capacities, personality characteristics, emotional regulation, skills, memories, and relational roles.
ABI introduces a formal distinction the framework has not previously required: landscape alteration (ℒ_post ≠ ℒ_pre) versus landscape displacement, with S°_pre potentially unreachable not because of attractor dynamics but because the structural substrate encoding it has been physically altered. The neurological identity discontinuity generated by ABI — particularly frontal lobe injury — produces a double grief: the person with ABI grieves for their pre-injury self while family members experience ambiguous loss (Boss) for the person they knew.
The rehabilitation landscape is formally characterized by four temporal phases (acute, subacute, plateau, chronic) with rehabilitation targeting S°_post construction rather than S°_pre restoration. Secondary wrong attractors (depression 40-50%, anxiety 25-50%, PTSD, pseudobulbar affect, behavioral disinhibition) are identified as more immediately actionable than the primary neurological deficit.
Anosognosia is formalized as sensor damage: D̂(ξ) ≈ 0 when D(ξ) ≫ 0, requiring external anchoring rather than self-navigated return. Caregiver and family system displacement is formally modeled. Nine formal propositions are derived. CTE (chronic traumatic encephalopathy) is analyzed as slow-accumulation landscape alteration through repeated subconcussive impacts.