Passive vs. active attention

Lectures are usually scheduled to last around an hour, and what students are doing during most conventional lectures involves 'passive' attention (such as listening and recording some of what is said or displayed visually). When we are being largely passive our brains have a limited capacity to maintain attention and maximise performance for very long.

Attention graphs

Attention graphs are a good way of illustrating this point. They are schematic graphs that represent attention during an average one-hour lecture, the horizontal axis indicating time (an hour) and the vertical axis indicating the level of student attention or performance. In research studies, 'performance' might be indicated by:

  • The proportion of that part of the lecture that is recorded in students' notes
  • The proportion of worthwhile information students can recall, or questions students could subsequently answer about that section of the lecture.


Different students in different lectures might display a somewhat different pattern, but the graphs represent an average. They are based on studies reported in Bligh (1998).

The following graphs and descriptions show how attention varies, and how this can be affected by the introduction of more activity for the student.

Dramatic decline graph

This graph shows student performance up the Y axis and the lecture time (up to 60 minutes) along the X axis. The line of the graph decreases sharply as the lecture progresses, with a slight increase towards the end.

Normally after an initial period of relatively high levels of attention, students' performance drops off markedly to quite a low level after as little as 10 to 12 minutes, and remains at a low level until an increase near to the end of the lecture. There is nothing magic about 60 minutes – if the lecture is shorter, then this increase starts just before the end whenever it happens. Much of the middle period of a lecture can be pretty much a waste of time unless you do something to improve students' attention.

Decline, recovery and decline graph

This graph shows student performance up the Y axis and the lecture time (up to 60 minutes) along the X axis. The line of the graph declines up to and including a rest break. It then rises sharply after a rest break when a new activity is introduced, before declining again and rising slightly at the end of the lecture.

If you were to introduce a break, or even better a very different kind of mental task for students, then attention can be restored to near its original level, but it declines again once you restart lecturing. The kinds of tasks you might introduce include a short problem to tackle or a short discussion with a neighbour.

Three declines and recoveries graph

This graph shows student performance up the Y axis and the lecture time (up to 60 minutes) along the X axis. The line of the graph shows three declines and peaks in student performance owing to the introduction of several breaks or changes in activity.

If you introduce breaks or tasks about every 15 minutes, preferably a variety of tasks that make different kinds of mental demands, then effective attention can be maintained for quite long periods. In this graph the green shaded area represents the gain in student performance from stopping lecturing for short periods and this gain greatly outweighs the loss from the few minutes of not lecturing.

Horizontal line graph

This graph shows student performance up the Y axis and the lecture time (up to 60 minutes) along the X axis. The line of the graph is consistently high for the duration of the lecture.

We have all experienced wonderful lectures where, without any breaks or activities, we were captivated and engaged at a high level throughout. However, this is clearly a rare phenomenon amidst students' daily grind of attending one lecture after another. You may be lucky enough to be a captivating speaker.

What this means for lecturers

As the graphs and descriptions show, for those of us who are not already brilliant and charismatic lecturers, tackling the normal decline in students' attention is one of the most obvious ways to improve student learning in lectures. The trick is, every so often, to change the nature of the mental demand made on students and to turn passive attention into active learning. How to do this is addressed in 'Lecturing 2'.

Assessing attention

It may be obvious that students are slumped and not paying attention after a while. But if it is hard to tell, then collect up several sets of notes at the end of the lecture (not from the students in the front row!) and have a look to see if the proportion of your talk that is recorded declines as the lecture progresses. Reassure the students that it is your lecture that is being checked on, not their note-taking. It is common for the middle sections of a lecture to be accompanied by very sketchy student notes, reflecting low levels of attention.

Directing and holding attention

As well as ensuring that students are actively involved in the lecture, another way of combating drops in concentration is to make a special effort to grab students' attention in the first place and then hold it. Techniques include:

  • Directing attention to key points: "Whatever else, make sure you notice this section of the problem solution here, which is important because..."
  • Directing attention away from competing demands: "OK, please stop writing notes for a moment and just watch how I tackle this problem..."
  • Using a format of presentation such as a puzzle or a story, where students will want to know 'what happens next'
  • Shifting from one format of presentation to another: "I'm going to be quiet now so that you can watch this brief video demonstration."


Consider the following scenario. Pause before reflecting on our own thoughts on how you might respond.

Scenario: Imagine that you have been lecturing for 30 minutes and you look up and notice that half the back row is slumped on their desks and others are looking distinctly sluggish. You haven't prepared any questions or activities. What do you do?

Our thoughts: The easiest thing is to announce a break: "OK, we've been bashing on for half an hour, let's take a quick break. Stretch your legs, have a chat, I'll start again in two minutes." If you feel reluctant to give them two minutes off, ask them to work on their notes, e.g. "OK, I'm going to give you two minutes to catch up with your note-taking. Check with the person next to you that you have got everything you need written down accurately." You will probably benefit from the break as well.


More ideas about how to introduce activities that break up a lecture and restore attention can be found in 'Lecturing 2'.