Increased MMN amplitude following passive perceptual learning with LTP-like rapid stimulation.

An important feature of perception is plasticity, enabling the acquisition of new perceptual representations to facilitate responding to regular stimuli in the environment. The auditory system has shown capacity for plasticity into adulthood, allowing the perceptual discrimination abilities to be improved by training. It has been suggested that a certain form of passive learning using rapid sensory stimulation can lead to plasticity in the sensory cortex through mechanisms similar to long-term potentiation. Here we demonstrate using electroencephalography that brief rapid auditory stimulation (2 min, 13 Hz) with a sinusoidal tone (1025 Hz) led to increased discriminability of the stimulated tone from a standard tone (1000 Hz) as indexed by mismatch negativity event-related potential. This shows that perceptual learning with brief exposure can cause plastic changes similar to long-term training.