CamKII positive autofeedbackloop

One proposed mechanism of memory formation and learning is activity dependent strengthening of synapses. Long term potentiation or LTP is one theses mechanisms.

Calcium/Calmodulin -dependent protein Kinase II is a protein present in the brain and activated during LTP. Once activated, it auto-phosphorylates once this positive autofeedback is tought one of the causes of LTP and memory formation.

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review article

[ http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=281742 link]