“Some people talk in their sleep. Lecturers talk while other people sleep”. Albert Camus
The lecture — a one-two-hour-long, one-size fits all, largely passive, transfer of information — remains the most widely used method of education at schools and colleges worldwide. It is a ritual that has been repeated for hundreds (if not thousands) of years. Students, parents, and educators assume the lectures have been very helpful (especially if the lecturer is famous or a great orator).
However, beginning in the 1960s, research in cognitive neuroscience and psychology turned these assumptions upside down. Thirty five years ago Johnstone and Percival observed students in over 90 lectures, given by 12 different lecturers. They noted the longest attention span in a lecture was about 18 minutes and that during a lecture there were many periods of inattention such that by the end of the lecture, attention had dropped to 4 minutes. Hartley and Davies, in a 1986 paper, noted that after a lecture, student’s recall of facts from the first 10 minutes of the lecture was more than three-fold higher than from the last 10 minutes. These studies suggest that how good or bad a given lecturer is has only a small bearing on how much information students retained after a 60 minute lecture — much of it is determined by how our brains are wired to process information.
Another insight from neuroscience research is the surprising finding that learning is a highly individualised process — after hearing the same set of facts, every student creates his /her own meaning and a unique set of memories, based on his/her own beliefs and experiences. In other words, information cannot simply be transmitted passively from one mind to another, like say we can with a music file. Research also shows that passive teacher centric instruction does little to develop problem solving skills — a reason why companies increasingly find that today’s graduates are not prepared for the work force and end up having to retrain them.
Clearly there are many factors that affect learning, and as with any field there are disagreements about some of the research findings. But in today’s hyperconnected environment with an abundance of distractions, the attention span of a student is likely to be compromised even further than it was several decades ago. In a recent poll of 1,000 students, the self-reported average amount of concentration during lectures was a mere ten minutes!
If students zone out for significant portions of most lectures and if what was learned in the first part is erased during the second half of the lecture, then clearly long lectures are not the most effective tool. Why then is the 60 minute lecture so prevalent?
Before printed books were widely available, note taking during lectures, with or without understanding the material, was a means of gathering information. Lectures became widespread in the 1700s when the Kingdom of Prussia launched an 8-year basic primary education programme to prepare the masses for a growing industrial workforce. Subsequently this model of education spread throughout the world for both school and college education, and remains largely intact today due to habit, resistance to change, and ignorance of the alternatives.
What’s the alternative? Active or experiential learning — a form of learning that requires students to reflect and apply ideas in solving problems. It is more student centric and often involves collaborative (peer) learning. How good is the evidence that active learning is better?
One of the most impressive demonstrations is from a 1998 study that compared 2084 students taking 14 traditional science courses versus 4458 students taking 48 “interactive” active learning courses. The study found that measures of conceptual understanding were vastly superior in the active learning group — by a margin of 2 standard deviations! Many other studies, across multiple fields, show that active learning outperforms passive teaching.
Change is coming and many leading institutions are beginning to de-emphasise passive learning. For example, at Duke-NUS medical school in Singapore, unlike traditional medical schools, students learn before coming to class (through online materials and lectures), take a test when they come into class to ensure they do the pre-reading, sit through a short 15 minute lecture and then retake a test. They then apply the knowledge to solve case problems in small teams.
An active peer learning model is also now being adopted by high schools — at the Spectra Secondary School in Singapore, several weeks of class lectures are made available online so students can progress at their own pace and even ahead of the class. Quick learners of mathematics can help their fellow student slower learners individually.
By reducing time spent in passive lectures, colleges can free up time with more active problem solving and team based learning strategies. The return on investment from tuition and education would then be greater to both the student and society. To empower the next generation of students, we would do well to heed theobservation by Sophocles that, “ one must learn by doing the thing, for though you think you know it, you have no certainty until you try”.
DR. P. MURALI DORAISWAMY, DR. MOHAN CHILUKURI, DR. K. RANGA KRISHNAN
(Murali Doraiswamy is a Professor at Duke University; Mohan Chilukuri is a physician and educator with the University of North Carolina; Ranga Krishnan is the Dean of the Duke-NUS Graduate Medical School, Singapore)