There are many ways that sound can influence memory, but researchers in Germany are finding that the precise application of particular sounds can improve recall and retention on a reproducible basis. The implications of this discovery are vast, but they hold out real hope that we will be able to use our musical knowledge to expand our mind’s capacity.
Research indicates that synthetic sounds such as music, when matched precisely to the brain’s oscillatory pattern during precise periods of sleep, consistently improve the ability to recall a list of words that was memorized just before sleeping.
During some parts of sleep the brain goes into a “slow-wave pattern” that are made of large amounts of unified brain activity known as Delta Wave patterns. This is the period of sleep immediately before “Rapid Eye Movement” sleep. The body relaxes during this phase and the brain triggers itself in large movements involving multiple banks of neurons. Healing and tissue repair often occur during slow wave sleep, as does the formation of long term memories. The mechanism by which this is accomplished is not yet completely understood.
Sleep researchers at the University of Tübingen have found that if the slow-wave pattern is determined and sounds that mirror them are played in the sleeper’s hearing, then memory retention can improved. A long range study with eleven participants tested their ability to recall lists of words and word associations that they had memorized immediately before sleep. As they slept the researchers stimulated them with “placebo” sounds as well as direct reflections of their slow-wave sleep patterns.
Subjects who were presented with the proper sounds at the proper times found that their ability to remember the word associations was markedly improved. Placebo sounds and sounds played at the wrong moments had no such effect. The sonic stimulation must occur during the slow-wave phase of deep sleep, and the sounds must be synchronized with the individual oscillatory rhythm of each sleeper. Without these conditions the sounds had no measurable effect on the memory.
The elegant simplicity and practicality of this method is not lost on the researchers. Dr. Jan Born, one of the authors and administrators of the research project, says that the non-invasive technique of this method makes it uniquely ethical and easy to administer. Direct electrical stimulation, the previous gold standard in memory improvement experiments, is extremely difficult and raises difficult questions of medical ethics.
Sonic stimulation, such as music, is entirely without drawback. Since music is more effective than direct electrical stimulation there is no reason that it should not become the new method of choice to improve sleeping rhythm and assist in the long term retention of memory. Born add that if the sonic stimulation is applied during the “up state” of the slow-wave period it makes the slow oscillations stronger. Their amplitude increases and they occur for longer stretches of time. This deepens the sleep and strengthens the natural processes that occur at this phase. This has tremendous implications for those who have difficulty achieving the deeper stages of sleep.
Once this research is finalized and codified it holds out tremendous hope for people who want to use music to improve their memories. The equipment required to carry this out is available in every home. Music, properly applied, will be able to expand their memory and deepen their sleep. The precise application is not yet certain, but researchers know that it will be soon. Deeper sleep and a clearer mind are one-well placed song away.