Permanent memory

Permanent memories are thought to be stored in the cortex, but little is known about the molecular and cellular processes that incorporate memories into cortical networks. In 17 May Nature, Paul Frankland and colleagues report that the enzyme α-calcium-calmodulin kinase II (α-CaMKII) is required in mice for the consolidation of memory (Nature 2001, 411:309-313).

Mice that are heterozygous for a null mutation in the gene for α-CaMKII showed normal learning and memory 1–3 days after training, but 10–50 days later the training was forgotten when compared with wild-type mice (p<0.05). The α-CaMKII heterozygotes performed well in a water maze — a test of hippocampal learning — suggesting that the mice have impaired cortical, not hippocampal, long-term potentiation.