Tau pathology in chronic traumatic encephalopathy (CTE). In addition to neocortical tau pathology, tau-immunoreactive profiles are common in the hippocampus in CTE, with preferential involvement of sector CA2 by neurofibrillary tangles and extracellular tangles, as well as astroglial tau pathology (a, 59-year-old male, former soccer player). Elsewhere, tau pathologies are described in the deep gray nuclei and brainstem, where tau-immunoreactive substantia nigra neurons and neurites may be present, together with a degree of pigment incontinence (b, same case as in a). Scattered tau-immunoreactive axonal profiles are also common in subcortical and midline white matter (c, same case as a; d, 60-year-old male, former boxer). All sections stained for phosphorylated tau using antibody CP-13 (courtesy of Dr. P. Davies).