Synaptic scaling. Synaptic scaling involves global adjustments of all synapses in a neuron in response to global changes in neuronal activity. Decreases in neuronal activity lead to global increases in synaptic efficacy in the target neuron (upscaling). Increases in neuronal activity lead to global decreases in synaptic efficacy in the target neuron (downscaling). This form of plasticity is considered “non-Hebbian” because it involves global adjustments of synapses, rather than input-specific changes in discrete synapses.
