We may be familiar with the concept of electrical/chemical signals relating to neural communication. So, now imagine of every synapse branching out from every neuron - like an antenna, is tuned to a different frequency signal with a specific optimal point and this optimum frequency point depends on the location of the synapse on a neuron. The farther away the synapse is from the neuron’s cell body, the higher the optimum frequency was found to be.  And it seems the more rhythmically synced the frequencies were - the stronger the connection for memory and learning synapses.

 The researchers found that not only does each synapse have a preferred frequency for achieving optimal learning, but for the best effect, the frequency needs to be perfectly rhythmic — timed at exact intervals. Even at the optimal frequency, if the rhythm was thrown off, synaptic learning was substantially diminished.

Their research also showed that once a synapse learns, its optimal frequency changes. In other words, if the optimal frequency for a naïve synapse — one that has not learned anything yet — was, say, 30 spikes per second, after learning, that very same synapse would learn optimally at a lower frequency, say 24 spikes per second. Thus, learning itself changes the optimal frequency for a synapse.

As well as possibly strengthening and enhancing learning and memory, learning-induced re-tuning and de-tuning could be have “important implications for treating disorders related to forgetting, such as PTSD disorder”. Read more here.