Residual perception of moving objects: dissociation of moving and static objects in a case of posterior cortical atrophy.

BACKGROUND/AIMS: Several studies have reported specific cognitive deficits of posterior cortical atrophy (PCA) starting in the early stage; however, these characteristics have not been demonstrated as arising in the middle or late stage of the disease. We report a patient with PCA who exhibited atypical symptoms after the middle stage.

METHODS

We observed and examined the patient for more than 10 years in clinical and everyday situations.

RESULTS

With increasing symptoms, the patient gradually showed blind-like behavior. He could not find a static object even when it was in front of him, but he could see and catch a tossed ball very well. In addition, he could walk and pick up scattered golf balls without colliding with obstacles. Magnetic resonance imaging and single photon emission computed tomography indicated severe degeneration in the white matter of the parietal lobe and lateral occipital region, whereas the primary visual cortex was relatively intact.

CONCLUSION

Several studies have reported specific cognitive deficits in PCA; however, the present results support the conclusion that not only the initial stage but also the middle and late stages of the disease have the potential to disturb specific cognitive systems.