Figure 2 Cognitive decline and medial temporal lobe width for all participants with anterior‐medial thalamic hyperintensities ⩾5 mm³. Anterior‐medial thalamic hyperintensities >55 mm³ (horizontal line) resulted in a sudden onset or decline of cognitive function in 10 of 11 people. Smaller AMT hyperintensities (<55 mm³) in people with medial temporal atrophy (<12.0 mm) did not correlate with an acute change in cognitive function; in contrast, similarly small AMT hyperintensities (<55 mm³) in people without medial temporal atrophy did result in sudden decline (bottom right of graph).