The most effective way to obtain long-term memory is to increase first presentation duration of single words

Still, too little is known about the limits of human knowledge; and especially about the means to transmit it amongst learners. We lack an optimal theoretical protocol of presentation of notions in order to promote the most effective and efficient long-term retention. The aim of our study is to find a method to measure and quantify physiological learning time in human beings, and, in particular, the reinforcement schedule needed to obtain the so-called memory consolidation. 54 healthy volunteers aged 18–31 years old were asked to read and repeat 5 foreign words with different alternative protocols and the retention of the words was then evaluated after 1 h, 1 day, 10 days and 30 days. The results showed that the time spent for the first presentation of each new information and the amount and spacing of its iterations increase the probability of consolidation for that information, in accordance with the known greater efficacy of spaced learning, but suggesting that the best protocol for learning consists of very few (i.e. 1–2) new ‘things’ to learn at a time.