Posterior Cortical Atrophy (PCA)

Posterior Cortical Atrophy (PCA) (also known as Benson’s Syndrome), is a rare, visual variant of Alzheimer’s disease. The disease primarily affects areas in the posterior regions of the brain (parietal, occipital, and occipitotemporal cortex) responsible for complex visual processing, spatial perception, spelling, and calculation. Unlike in typical Alzheimer’s, memory and insight are usually preserved in the early stages of the disease.

  • The individuals with PCA are more commonly women.[1]
Risk Factors
  • Individuals with PCA often have simultanagnosia, an inability to perceive multiple visual locations simultaneously or to shift attention from one object to another
    • This results in a very restricted effective visual field where it is like “looking at life through a telescope” (or “missing the forest for the trees”)
  • Finger agnosia (inability to tell apart fingers on the hand)
    • The individual cannot tell the difference from their thumb and index, middle, ring, pinky finger
  • Left/right indiscrimination (inability to tell left from right)
  • Acalculia (difficulty with calculation) and agraphia (loss of ability to write)