Flexibility in the brain allows us to adapt and learn, by creating new connections between neurons, known as synapses, or strengthening the links we use most. Recent research following levels of a protein called Arc suggests that this process is balanced out by losing other connections. Neurons receive input from other cells through synapses along the branches, or dendrites, of a complex web of cellular protrusions known as the dendritic tree. This video shows signals, in green, starting at different points along a dendrite (in red) in the brain of an active mouse. Experiments manipulating neurons responsible for vision showed that stimulating one particular connection increased the synapse’s strength, while nearby synapses diminished. Strengthened synapses displayed low levels of Arc protein and more signal receptors, while weakened synapses featured fewer receptors and high levels of Arc, suggesting a mechanism by which this critical balance is maintained.
Written by Emmanuelle Briolat
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