When you can recite a poem but not remember who asked you to learn it a few days earlier

Dr. Claire Bindschaedler and Dr. Claire Peter-Favre from the Neuropsychology Unit of Lausanne's University Hospital in Switzerland, together with their colleagues Prof. Philippe Maeder, Dr. Thérèse Hirsbrunner and Prof. Stephanie Clarke, investigated the case of a patient known as VJ, one of the few cases of developmental amnesia reported in the scientific literature. Repeated neuropsychological testing showed that VJ cannot remember being read a story or shown a picture half an hour earlier, or at least remembers little of it. At the same time however, VJ does do well on tests of general knowledge, also called semantic memory. In fact, when tested regularly over his childhood and teenage years, VJ was found to develop at the same rate as other children in areas of general knowledge and general intelligence.

Analysing MRI scans of VJ's brain, Dr. Philippe Maeder found very severe atrophy (wasting away of brain tissue) in the hippocampi, while the adjacent area of the brain, known as the perirhinal cortex, was relatively spared from damage. This latter area is hypothesised to be important for the acquisition of semantic memory. These findings lend support to the idea that episodic memory (but not semantic memory) depends on the hippocampus.

More information: The article is "Growing up with bilateral hippocampal atrophy: From childhood to teenage" by Claire Bindschaedler, Claire Peter-Favre, Philippe Maeder, Thérèse Hirsbrunner, Stephanie Clarke, and appears in Cortex, Volume 47, Issue 8 (September 2011)

Provided by Elsevier