Rules of thumb for presentations – how good are they?

Photo Flickr – by Lintmachine

People like formulas. They are expedient rules of thumb that guard against dangerous extremes. “Plan for one minute  and a half per slide”, some say, “and never put more than 5 bullets point and more than 5 words per bullet point”. Under these rules lie hidden assumptions about people’s attention span, prior knowledge of the presented topic, text readability, number of clicks needed to go through the material on the slide, audience interactivity, and more!  Presenters could be fooled into thinking that as long as these rules of thumb are followed, their presentation will be fine.

Rule of thumb #1: “Plan for one and a half minute per slide” is about as silly as telling a writer “Plan for chapters with 20 pages”. What is the purpose of this rule? It prevents presenters from putting so much information on one slide that to cover it would take more than 90 seconds. It also prevents boredom: people don’t generally like to stare at the same information for a long time. They get bored because they can read faster than the presenter can speak. Spending three minutes explaining each bullet point is as effective as administering a sleeping pill. What is important here is visual interest, not screen-time. A 30 second slide that gathers interest is fine. A two minute slide that exploits a particularly fruitful visual is fine so long as interest is maintained (let the audience be the judge of that through their questions). A slide that dynamically reveals and removes information through the use of layers can last a very long time, and it’s perfectly fine.

Rule of thumb #2: “Use not more than 5 lines and 5 words per line” (some say six lines, some say four; some say six words per line…). This is silly too, particularly in scientific presentations where long compound nouns abound. So what is the purpose of this rule? 1) to decrease the amount of text on a slide, so that the slide remains readable; 2) to prevent long lists that remove the need to try and select what is important and leave out what is less important; 3) to force the presenter to be concise as opposed to verbose; and 4) to allow the slide to be presented in less than 90 seconds; and thus maintain visual interest by not keeping the same slide on the screen too long – a point already covered above. What is important here is, again, the “Less-is-more” principle: the need to be selective to be  legible, AND to be intelligible (clear), and finally, the need to keep visual interest with something other than words.

There is however one rule of thumb I like… but then again, because it works for me does not mean it works for you. This rule of thumb is based on your arm length and your palm size. It determines whether the text on your slide will be readable once projected on the large screen in front of your audience. Readability of text is not to be decided on the grounds that you can read everything on your PowerPoint slide, while sitting one foot away from your computer screen. High screen resolution and brightness will even allow font size 7 to be readable! So if your arm is long enough and your hand is not super tiny, and most of all, if you do not look like a chimp, this rule of thumb might work for you.

Start your slideshow. Stretch out your arm and turn your hand horizontally, fingers pointing to your left if you are right handed, and vice versa. Move away from your computer screen until your stretched hand hides the screen. Remove your hand (but do keep it at the end of your forearm) away from the screen. If you can read everything on the screen from that distance, chances are your audience will be able to read it too, once that slide is projected. Oh, by the way, if you really want to be sure, turn down the brightness of your screen to 50% and move back one half meter more 🙂

By Jean-luc Lebrun


Effective Variant on the Assertion – Evidence Paradigm

The Assertion – Evidence paradigm, promoted by Michael Alley, does indeed force the presenter to limit the information on each slide (and less is mostly more, even in scientific presentations – see limitations). But does Assertion follow Evidence, or Evidence follow Assertion as in the traditional scientific order? To determine which order is more effective, I seeked the opinion of the scientists in the audience during my communication skills seminars. Some do not care about the order. But some prefer to see the evidence before an assertion is made – particularly if a question is raised prior to showing the enlightening visual evidence. When asked to probe this visual evidence for answers, their mind leaves the passive show-me mode to enter the active let-me-see mode. They are more involved and interested. When they discover the yet-to-appear assertion by themselves, under the friendly guidance of the presenter, they are more likely to be convinced by it and more likely to remember it when it is revealed.

Food for discussion.

Here is an example:





Text and visuals by Jean-luc Lebrun

020 The TED presenter

The Apple flag gives you a hint. Our next guest is from Apple, in Cupertino California. His name is Ken Eddings – and he is the man behind Apple’s DNS. But it is not the IT guru I are interviewing, it is the Ken Eddings who frequently attends TED conferences worldwide… reason is, he provides technical support for its organizers. To those of you not familiar with TED, I recommend you go to their website:; TED advertizes itself with the slogan: “Riveting Talks by Remarkable People”.  So it was interesting to get Ken’s perspective on what is a good TED presenter, and on the type of technical issues he had to face while supporting TED talks.

By Jean-luc Lebrun

Is “Less is more” a presentation law as universal as the law of gravity?

Image Flickr. Cesar Rincon. “There is no spoon”

Most people who browse websites covering presentation skills stumble on the maxim “Less is more“. Usually, this principle applies to the content of PowerPoint slides. Less slide (text) content to be read by the audience is seen as more beneficial to the speaker. As scientists, we should question everything, right?

Those of you who are LinkedIn members will find an excellent discussion on this principle in the “Presentation Gurus!” discussion started by Matt Gambino entitled “Ways to convince co-workers that “less is more” in PowerPoint”.

Generally, I agree with the “less is more” principle and promote it in my courses. Why? The more there is on a slide, the more that slide has separate areas of focus. The problem then becomes one of synchronicity between the oral comment of the speaker and the visual focus of the audience on the part of the slide that visually matches the oral comment. Perfect synchronicity is impossible in practice. Either we linger on points for which we have insufficient prior knowledge while the expert speaker moves on to other points. Or we disagree with the point made and stop following the other points, constantly returning our eyes to the point of contention. Or the speaker fails to verbally or visually identify on the slide the target where our attention should be focused, imagining that we are able to use our knowledge or his speech to figure it out by ourselves. Most of us, non-experts, can’t.  To reduce such synchronicity problems, presenters use layers, laser pointers, they introduce one bullet at a time, or they make each bullet become one slide. The problems are reduced, but not to the point they disappear!

So… Let’s start questioning the assertion “Less is more”, as scientists.

1) Is there a lower boundary to less under which less is less?

Clearly, one cannot push the limit past a certain lower boundary beyond which, slide support is no longer effective. The sketchy or vague information on each slide may become so cryptic that the oral comment is bound to go beyond the slide content, thus creating an attention divide between slide content and oral content.  Research shows that, in such situations, memory is less effective and brain activity is lesser than under full undivided attention (encoding slows down in the”hypoccampus, temporal and prefrontal cortex of the left hemisphere*”).

The lower boundary is also defined by the interdependencies within the points made on a slide. When a slide makes multiple inter-related pojnts, these points must remain on the same slide for the audience to see the interdependencies. In this case, less, would force the presenter to divide the slide into multiple slides, and that in turn would force the audience to remember the contents of the previous slides to be able to see the interdependencies. In reality, we don’t remember. Working on making slides independent of each other is a move in the right direction.

The lower boundary is also influenced by the gap between the prior knowledge level of the audience and the knowledge level expected by the speaker. If that gap is large, less “just in time” background information, results in less understanding.

2) Are there situations where, clearly, less is not more, but more is more?

I can think of at least four situations where this would apply:

If providing less contents does not fulfil the expectations your slide title raised in the audience (even the title of your talk), more is more as the speaker needs to meet the expectations that any slide title raises.

For the second situation, imagine a scientist with an accent so thick that the audience understands less than a quarter of the words pronounced. In this situation, the scientist could say less, and possibly read more or display more while giving ample time to the audience to read along and to figure out what the graphics contain since graphics are usually understood regardless of language for the most part.  They are vital when it comes to understanding and essential when it comes to convincing. In this case, the audio track is not essential as long as the video track is self-explanatory. More (legible) text on a slide would bring better understanding. Since the memory required to associate the sounds heard from the speaker with the written words on the slide is far too large, the audience rapidly gives up and reads.

A third situation arises when we consider that, since the lack of synchronicity is one of the causes for the “less is more” principle, the speaker can increase synchronicity by slowing down the pace, but also by adding arrows, circles, and other attention-calling methods such as callout boxes, colour /size change, animation, etc. In this case, more is more.

Lastly, my fourth example is inspired by an earlier comment of Ed Skarbek: more is more if you have access to more than one screen to visualize your information, and facilitate comparisons – assumed here is that the extra screens carry visuals, not just text.

I hope this provides a more balanced perspective to the “Less is More” maxim.

By Jean-luc Lebrun

“The Effect of Divided Attention on Encoding and Retrieval in Episodic Memory Revealed by Positron Emission Tomography”. Tetsuya Lidaka & Al,*Journal of cognitive neuroscience archive. vol.12. issue 2. March 2000,p267-280

Presentation traps 7 – the cultural trap

Image from Flickr; “The return of Edward Hyde” by Luis Carlos Arauio.

I have much respect for authors who go to great lengths to get an attractive title for their  paper. “The Inflammatory Macrophage: A story of Jekyll and Hyde”* is a fantastic title… for westerners familiar with Robert Louis Stevenson’s 1886 book “The Strange Case of Dr.Jekyll and Mr. Hyde”. Now imagine the biologist from a chinese university reading that title for the first time. What will he do? Search for these two scientists, Dr. Jekyll and Dr. Hyde, in the reference section for their journal publications? Will the search be fruitful? Beware of cultural icons, in your title or in your talk.

For the sake of clarity, do not use metaphors or expressions that are meaningless to a foreign audience. Take baseball language, for example. It is understood by a few nations only – The scientist who claims his lab is batting a thousand in proteomics research, and has all its bases covered is certain to lose Dr. Pierre Lebrun, and Dr Xiao Hong. I remember buying the book “Playing for Pizza” written by my favourite author John Grisham. I could not understand a thing. The baseball language effectively excluded me from most of the story.

For the sake of clarity, do not display your extensive culture by using a sophisticated word where a simpler one exists. Doing so creates a distance between you and your audience in terms of understanding (common word) or comprehension (sophisticated word). Think audience. The scientists attending your talk may have good knowledge of the keywords used in your domain, but they may not have your culture. French presenters, beware. To the native English speaker, you seem to use a very sophisticated English during your talk, when in fact, you use words that are in your everyday French language, pronounced “à la sauce anglaise“. And now you have another example of such mis-behaviour: using foreign words to display your extensive culture. If you want to know why the French seem to speak such polished English, (hint: it started in year 1066 Anno Domino) – Beautiful latin, isn’t it? Sorry, I’m manifestly getting off base on this one. ARGH! I think it’s time for a tin of spinach – Hey, Popeye!

By Jean-luc Lebrun

*JS Duffield, the inflammatory macrophage : a story of Jekyll and Hyde, clinical science (London). 2003 Jan ;104(1) :27-38

Presentation traps 6 – the conclusion traps

Think about it. You have done your best to gather the interest of your audience around your topic for a full eleven minutes. The chairperson just looked at his watch, and corrected his sitting position to move closer to the microphone. Your talk officially ends in one minute. If you play the prolongations, it will be at the expense of your three minute Q&A time during which you intend to identify who else is interested in your research for later networking opportunities. You want to keep to time. So far, so good. You bring up your conclusion slide… and you are in danger of falling into one of three conclusion traps.

1. Your conclusion slide is a summary of your results.

2. You know you are close to the end of your talk, everything has been said, and you rush through that slide, simply reading its bullets.

3. You do a great job with your conclusion slide, and after clicking one last time the next slide button on your presentation remote, you land into one of the following slides: a) the black screen indicating the end of your presentation (a PowerPoint feature); b) the traditional Acknowledgment slide; or c) a black slide on which the words “Thank You” are written in Font size 88 – for good luck 🙂

Everything you have read so far does not explain why the image used in this post (Source Flickr, author Shenghun Lin) is that of someone running a relay race. You are about to discover why.

Conclusion trap 1 – the blind hand-over of the relay baton

The conclusion is the place in your talk where you will hand out the relay baton to those in the audience who could benefit from your scientific contribution. You want these people to read your paper, or to ask you questions, or to network with you at the end of your presentation. And you certainly want them to know how what you have discovered can be of value to them. Therefore, the conclusion slide is not about your results, your research outputs; It is about the audience “Take-Away”, your research outcomes. That is why I used the metaphor of a relay race. With your conclusion, you will hand out the part of your research that is directly applicable to the people in the audience. You might argue that “anyone is able to judge the impact of my work. I do not need to state it.” What you say is true for the experts in the room. The non-experts, however, are often unable , for lack of knowledge, to determine what these outcomes are, and how they are of value to them. You must see the hand of the next runner. You must have identified and thought about the people who were the most likely to benefit from your work. Do not hand over the baton with your eyes closed!

Conclusion trap 2 – the dropped relay baton

Singers know that the two places in a song that matter the most, and which they rehearse the most, are the beginning and the end. Often, because presenters do not control their time well, they rush through the conclusion slide  (and read it). Or, because presenters are exhausted by the time they reach the end of their talk and want to end it quickly, they do not even bother to comment on that slide and let the audience read while they just thank the audience for their attention. There is no call for action, no USE MY RESEARCH FOR THIS OR FOR THAT. As a result, the relay baton is not properly handed over, it is dropped on the ground before the audience has had a chance to grab it. They may still do, but the momentum gathered through your words will be lost. What a crying shame 🙁 This time with the audience is face to face. It is a time to plea, to sell, to tease, to encourage, not a time to turn your back on the audience and read in a flat low tone. Surely, having rehearsed your conclusion slide so many times, you know by heart what appears on the screen after each mouse click, and never need to turn to it.

Conclusion trap 3 – the fumbled hand-over of the relay baton

The last slide of a presentation is the conclusion slide. Don’t fumble this. It remains on the screen until one of the questions demands that you bring another slide to the screen. The reason why it is not a thank you slide is because having the computer say thank you on your behalf is demeaning. You are the host; the computer is only there for support. The reason why your conclusion slide should not be a black screen is because you must help the audience remember the main perceived advantages of your research by maintaining the conclusion slide on the screen, at least until you move to another slide in answer to a question. And finally, the reason why the last slide is not the acknowledgment slide is because acknowledgments are best given on the title slide (see trap 5 – the title trap); furthermore, time may have run out and you may have to skip that slide anyway – thus risking disappointing the sponsors attending your talk.

in conclusion – make your conclusion slide:  the last slide, the most audience-centered slide, the most rehearsed slide.

By Jean-luc Lebrun

presentation traps 4 – the mouth trap

image source: Flickr. Fresh tomato sauce by Urbanfoodie33

It is the 10:15 am coffee break. Outside the meeting room is a long table covered in cream-coloured linen. On it the conference attendees find the traditional offerings: coffee, cream, Ceylon tea, brown and white sugar, and finger food to relieve the hunger pangs and make the long wait for lunch more tolerable. You did not join the people who left the room because it is your turn to present right after the coffee break. You are standing next to the computer. Your slides are ready. And you are waiting for people to come back into the room. Your friend walks in, slowly, holding a saucepan on which you see a cup filled nearly to the brim with piping hot coffee. she even thought of taking two sticks of your favourite raw sugar, and three small sealed cups of half and half cream. “Here, John. Take This. It will perk you up.” You smile, express your gratitude, move your hand towards the cup, and… STOP REWIND.

That  stainless steel pitcher of icy water glistening on the small table close to the lectern looks so refreshing. Condensation sends rivulets of crystalline water down its slippery sides. You are about to present. The glass in front of you is empty. You are a bit nervous and you think that drinking might water down that anxiety of yours. Your hand moves towards the pitcher, and… STOP REWIND.

The next day. You are also to present on behalf of your manager who missed his flight. His talk is right after lunch. The morning drags on but lunch finally arrives, and you are famished. You look at the buffet set out for the conference participants, and you see an irresistible spaghetti Bolognese dish between the roasted spuds with braised pork and the broccoli/cauliflower/mushroom/sweet peas mix. Your take the spaghetti serving spoon and lift it as carefully as a crane would lift its cargo prior to depositing it on your plate. Back at your table, you sit down, trap a wad of spaghettis between your fork and your spoon, and… STOP REWIND.

Can you say what might happen next in each scenario that may make your talk less effective?

Iced Water: Bad for your vocal chords. You need to warm them prior to a talk by speaking, not by drinking icy water. Drinking warm water is better for you, but hot coffee?

Coffee or tea: Prior to a presentation, your body produces the adrenaline hormone as a result of your anxiety. Coffee and tea contain caffeine, which helps the body keep that adrenaline of yours in your blood stream longer than it should. This is not wise. But milk?

Milk: The milk protein thickens natural mucus, such as saliva. Your anxiety may overproduce saliva which, combined with milk, thickens. As a result, your vocal chords feel as though something is getting in their way. They trigger a throat clearing reflex …while you are presenting, of course. And the sound-trapping lapel microphone you are wearing takes great pleasure in amplifying that unromantic sound to nauseating levels over the room speakers.

Spaghetti: The reason why the best restaurants offer a special towel for people who eat spaghetti is because the probability of decorating their guests’ white Armani blouse or shirt with red tomato sauce is fairly high. If the red sauce hits the target, be aware that trying to wash the stain away only contributes to spread it or, given enough water, to give you that wet t-shirt look … all this, right before your presentation, of course, with no time to return to your hotel room to change clothes. To prevent the audience from seeing the red stain, you will try to hide it in a number of different and creative ways while speaking; for example : facing the wall standing sideways,or turning your back to the audience, or holding some document in front of your chest during the whole talk… thus causing the audience to wonder what’s wrong with you !

So presenters, beware of the mouth trap. Drink warm water, avoid milk and coffee, and take a change of clothes if you intend to eat spaghetti!

By Jean-luc Lebrun

image source: Flickr. Fresh tomato sauce by Urbanfoodie33

Presentation traps 3 – the joke is on you

Photo Source: Flickr; Author: By Creativity+Timothy K. Hamilton

“Start with a joke”, “deride the audience”, “make them like you by making them laugh”, the pundits say. And out they go, on a limb as always, out go the serious presenters who end up being the only ones who laugh at the end of their jokes. The day before the event (it is easier to remember), they rush to the web for recycled jokes, or they try out the latest joke heard in a bar or at the canteen where everyone burst with embarrassed laughter. That joke often has sexual, religious, or racial connotation, and upon hearing it, the audience instantly moves from a I-am-neutral-towards-you state to a I-intensely-dislike-you state. Some may even get up and leave. I know you will say it never happens this way. Well, it does, and I witnessed such disastrous joke-telling at an international gathering of scientists. Some refrain from risky jokes and instead use self-deprecating jokes; after all, it’s ok to laugh at yourself, is it not? : “Good afternoon, ladies and gentlemen, or it might have been… had you been able to skip my talk and run to the beautiful beach in front of this hotel.” or ” I’m delighted to be the one who has been selected to help you sleep after today’s copious lunch. So I’ll do my best to make this talk as boring as I possibly can. Could we have the lights down now? Thank you very much.” The audience did not come to attend your talk expecting to be bored, but to discover new things. Your self-deprecating humour, will be translated by the audience as follows: “His slides are boring. He has not even bothered to rehearse his talk at all. He really doesn’t enjoy presenting to us, but he’s doing it because he has to.” To conclude, avoid jokes altogether at the start of your talk, even cartoons that may be funny. A play on word requires a good understanding of English. Idiomatic expressions, or culture specific jokes are beyond the level of comprehension of scientists with English as a second language or from different cultural backgrounds. If you want the audience to relax, use the only way that works 100% of the time: Face the audience, and SMILE 🙂


By Jean-luc Lebrun

Presentation traps 2 – Forced Audience Interaction

Source: Flickr; Photo by Jesarqit.

“Probe the audience”, “Interact with the audience”, the pundits say. And out on a limb they go, the misfortunate presenters for whom good advice but poor timing garner nothing but the deathly silence of  an unsympathetic audience. I recall the young scientist whose work featured the discovery of a gene associated with some sort of cancer. After introducing himself at the beginning of his talk, he probed the audience with this memorable question: “Has anyone here had a family member die of cancer?”

Naturally, the long silence that followed was not an indication that the audience was made of healthy individuals whose parents were healthy and grand parents were still in their prime. It meant that the presenter had frozen the whole audience. As he waited for his answer, looking straight at the audience, no-one spoke or raised a hand. He must have felt like the scientist listening to the SETI space probe waiting for a signal betraying intelligent life in the universe 🙂  for there seemed to be no life at all in this audience. What had he done wrong?

1) The question was too  personal and far too risky: What if one participant had replied: “Yes. My mother died of cancer last week.” What would the presenter have responded?

2) The timing was wrong. At the beginning of a talk, the audience is still in neutral gear, adopting a wait-and-see attitude, and certainly not yet ready for interaction.

At the beginning of a talk, the presenter has to move the audience out from a “Tri-State” or “high impedance” mode (infinite resistance) into a positive state (hopefully not a negative state).  The presenter has to make the current pass between him and the audience. To do that, two things are necessary. First, the presenter must open an invisible low resistance channel between his or her positively charged personality and the down-to-earth audience. And I know no better way to do that than by smiling and welcoming the audience. Secondly, the presenter must establish a difference in potential between him and the audience – for example, by creating a knowledge gap that the audience is eager to let him fill. The question is a good way to bring to life that knowledge gap, particularly an intriguing, provocative question or statement like Friedman’s assertion that “the world is flat”. But that question expects no answer from the audience. It is a rhetorical question. The presenter is expected to bridge the gap he created.

Do not rush the audience into action. An audience that has had time to be interested in both the presenter and his topic is easier to engage. By the time the talk ends, the audience is ready to interact through the Q&A: the time is right, and the audience is ready.

By Jean-luc Lebrun


Presentation traps 1 – Hazardous comparisons

With this, the first of several blog entries on presentation traps, we are entering the quagmires and the quicksands where many presenters get trapped. These traps are mostly concealed and presenters realise they are trapped far too late to fix the problem. These traps are avoidable because the ones who lay them are none others than…the presenters themselves.

(Photo source: Flickr – author: TheBusyBrain)

So let’s look at trap #1: the hazardous comparisons.

In your presentation, usually at the beginning in the motivation part, a  slide appears, and on that slide your method is compared to previous state of the art methods, or methods widely accepted and recognised as adequate by practitioners in the field. Of course, the comparison makes your work seem vastly superior. You feel good – after all, you are good and you have listed the weak points of other methods, either because you found out or because their authors had the intellectual honesty to recognise them.

Here is where things go wrong:

1) Because PowerPoint does not give you much space to illustrate each limitation, you simply list them all (it looks so good, doesn’t it :), in bullet point form, relying mostly on the use of adverbs, adjectives, and judgmental verbs to describe them: slow, computationally  intensive, unfeasible, limited, complex, expensive, fails to, suffers from…

2) In the room, attracted by your title, chances are you will find the very people whose methods you disparage: the experts, the “related work” folks. They came to learn from you, not to have their contribution to the field questioned or featured in a poor light.

3) Your summary judgmental evaluation on their methods is probably based on old reading, and the state of the art may have progressed much since you last looked at the related work papers, thus rendering our evaluation inaccurate at best.

As a result, your comparison strikes a match that will light the short fuse of the bomb bound to explode during your Q&A. These scientists you indirectly attacked will dispute or question your claims – because any adjective or adverb is a claim and a claim deserves fair justification before it can be accepted. Because the reputation of their work is at stake, they will bring you onto their turf – a place you know little about – and take great pleasure to demonstrate your ignorance through incisive questions!

So here are your solutions:

If you have to expose limitations:

Firstly, choose the main limitation, illustrate it visually and scientifically so that it cannot be contested, and make sure you clearly define the scope under which that limitation applies.

Secondly,  find a way to praise the method whose limitation you are presenting.

Of course, you do not have to expose limitations. Avoid comparisons altogether. If the experts are in the room, they will ask questions to assess how well your method is likely to work in their field (and this is good!). If you do not know, you will be able to deflect such questions on the grounds that you have not tried it there. At the same time, you will welcome their interest to see it applied in new fields and express your wish to collaborate to extend your method’s application scope – or discover its boundaries (don’t say limitations!). Again, if you don’t know, you could also delay your answer on the grounds that your data and their data may differ and that it would be better to compare apples with apples, and oranges with oranges before drawing conclusions.

Be conservative. Do not say “This method should also work in your field, or on your problem”, just in case they ask you the question “On which basis do you form this opinion?” if you answer is based on factual evidence, however early it may be, you will be seen as an expert. But if they detect a lie in your answer (it is often so because, from your angle, your perspective is distorted), you will be seen as a scientist of much enthusiasm but somewhat junior in experience. Look at the photo above, how much bigger the orange seems depends a lot on the perspective, doesn’t it. An architect who has studied perspective would have a more accurate answer than a researcher in life science. But someone who has handled both fruit would have the best answer.

Next trap: Forcing the audience to interact.

By Jean-luc Lebrun


021 Presenting to a lay audience

Today our podcast features Dr Cleo Choong. She had to give a presentation to members of parliament at the British House of Commons as part of a competition for the engineer of the year award. What is it like to present to such a prestigious gathering of elected congressmen? Did she win the competition? Find out how she handled this most difficult presentation.

source: Flickr, by vqm8383

Who is responsible for communicating the outcome of research

This question is explored in a community forum of the online journal “”. You will find it here

->The importance of good communication skills in science (you may need a subscription to access this page).

Here was my answer.

I would like to attempt answering this important question using two metaphors: Communication of a signal through an electrical network, and communication mediated by wind.

Communication as signal through an electrical circuit (Flickr – by Matthew Boyle)

The scientist who conducted the research is the source of the first signal in a long chain of networked communicators with various degrees of resistance, conductance, and amplification (managers, you are part of that chain – and you could be a resistor, capacitor, or amplifier).
One may argue that, without that sense of exaggeration brought by the “inflated view of the importance of their findings” described in an earlier comment, personal scientific communication would lack the energy necessary to pass through a network unable to easily distinguish signal from noise – even after peer-review. The communicator should indeed be in an excited state for a while. Otherwise, we would have to rely only on the characteristics of the signal transmission path in the network– a network whose amplification characteristics are often – and understandably – biased by the recognition of the success potential of the signal source.

Communication as wind (Flickr – by Hans s)

Naturally, there is chaff and there is wheat. And we need wind to separate the two. The wind of change is one, but also the gentle wind of well-targeted communication. Occasionally, if the impact is great, the wind of mass communication will kick up a storm great enough to blow away the chaff and seed productive ideas across a vast land, as well as return to fallow land parts of the sterile research landscape by depriving it from its life-sustaining grants.

To sum up: the responsibility is collective. Scientists need the press, but they also need to be aware of and energised by the impact of their research. As always, managers have a great role to play to facilitate this, but they need to understand that wind can also snuff a good candle, and that resistors always create heat.

By Jean-luc Lebrun

020 Telecom metaphor for effective scientific communications

Our new guest, Dr Francis Yeoh, CEO of the National Research Foundation, is drawing a useful analogy from the field of telecommunications to clarify the duties of the scientist who presents, and clearly define the conditions under which communication to an audience is effective. Transmitter, Receiver, Signal to Noise Ratio (SNR)… This fruitful metaphor will open your eyes so long as you open your ears… to this podcast!

(Flickr image by Woodleywonderworks)

continuity bugs in linear slide presentations

Whenever you take a non linear media and flatten it (make it linear), you introduce problems of two kinds:

1) Discontinuities in logic. The audience needs to remember what was connected to what, earlier in your presentation, to see the connection logic.

2) Discontinuity in time. As time passes, the audience remembers less and less of what they heard and saw. As a result, the memory fails to reconnect the time-broken strands of a disrupted argument.

Here is an illustration. Each square represents a slide. The slides are numbered from 1 to 5. The eroding effect of time on memory is here symbolized by the greying of colours, from dark (last slide best remembered) to grey (started to fade in memory) to dotted line (first slide, may have been presented 8 to 10 minutes before slide 5, vague or no longer remembered).

flattening problems

I assume here that all slides are equal in duration. Things worsen when slides are text heavy. We have all encountered slides that are so dense in information and take so long to explain that the audience has forgotten what was said at the beginning of the slide by the time the end of the slide is reached!

So here is my tip:

Visualize the logical connections between your slides, either as a domino or a graph. This will help you identify the potential memory-related problems your audience may face. And apply one of the following solutions to remove these problems.


The Announce technique consists in telling the audience what will be covered in the next (two) slides. The audience, once alerted, finds it much easier to keep the information of slide 1 in memory and relate it to slide 2 and 3.

The Repeat technique simply re-presents past information so as to be able to refresh fading memory (like the refresh cycle that keeps RAM memory alive!)

The Merge technique consists in keeping on the same slide all related elements, presenting them one by one (one at a time) to avoid overwhelming the audience with too much information at once, but allowing people to see past information on the same slide. Naturally, this is only possible if the slide can contain these related elements without losing readability.

The Restructure technique, as its name indicates, looks at alternative structures that would enable the contents to be presented without discontinuities.


By Jean-luc Lebrun

Learning from Henri Poincaré

Henri Poincarré

Henri Poincaré, the French physicist and mathematician was an outstanding scientist. In his book, La Science et la Méthode (Science and Method – Dover publication translated by Francis Maitland), he states that “to understand” means different things to different people. The scientists in your audience expect to be able to “understand” what is presented, so it is worth thinking about what people require to reach understanding. Poincaré identifies two classes of people: the validating and connecting type, and the associative and transformative type (my choice of words).

The validating and connecting type

“They want to know not only whether all the syllogisms of a demonstration are correct, but why they are linked together in one order rather than in another. As long as they appear to them engendered by caprice, and not by intelligence constantly conscious of the end to be attained they do not think they have understood.”

In other words, they need to see, understand, and find believable the fragmented evidence, but they also need to see, understand, and find believable the logical thread that connects these fragments together. Poincaré describes what happens when understanding is incomplete.

At first they still perceive the evidences that are placed before their eyes, but, as they are connected by too attenuated a thread with those that precede and those that follow, they pass without leaving a trace in their brains, and are immediately forgotten: illuminated for a moment, they relapse at once into an eternal night. As they advance further, they will no longer see this ephemeral light, because the theorems depend upon one another, and those they require have been forgotten.

You cannot memorize what you do not understand and further understanding stops as soon as memorizing stops.

Making sure that each slide in the presentation offers the right conclusions is not sufficient. The scientist who presents should also identify and explicitly reveal  and explain the logical connectors between any two consecutive slides.

The associative and transformative type

Others will always ask themselves what use is it. They will not have understood, unless they find around them, in practice or in nature, the object of such and such a mathematical notion. Under each word they wish to put a sensible image; the definition must call up an image, and at each stage of the demonstration they must see it being transformed and evolved. On this condition only will they understand and retain what they have understood.

Some may place more emphasis on evolution kinetics than on evolution logic.

These often deceive themselves: they do not listen to the reasoning, they look at the figures; they imagine that they have understood when they have only seen.

It is not sufficient to make sure that the content on each slide in the presentation is easily associated to prior knowledge and visually or conceptually connected to prior slides. The scientist who presents should also take the time to make explicit the reasons for the change in content from one slide to the next.

Since people understand things differently, the scientist who presents is well advised not to privilege one type of understanding (his own) over another. Therefore, to be effective, the presenter should do the following:

1) Since people need to validate what they see and hear at the level of a slide, give them the time to do so. Justify your logic, and ensure that each element on a slide is related to prior knowledge.

2) Because a slide delivers information in a discrete, and not continuous manner, each new slide introduces a discontinuity. Therefore, a bridge needs to be built between two consecutive slides. Verbally state the reason for the change in content that will be perceived by the audience.

By Jean-luc Lebrun

019 Dancing around outputs and outcomes

Did you ever wonder why your presentation, which looked and sounded awfully good, had little impact on your audience? The answer is found in this podcast… It is a matter of being able to tell the difference between a research output and a research outcome.

Learn more from our guest, Dr Leong Munkew, CTO of the SingaporeNational Library Board, a stellar presenter, and a brilliant technologist in the field of information retrieval.

(Photo by Zachstern, Flickr)

Blessed are the nitpickers

By Jean-luc Lebrun

If in every scientist lurks a nitpicker – a person who fusses over details – it is simply because scientific experiments require great attention to details. Nitpicking talents vary from one person to another. But, in any group of twelve people, I always have the good fortune to find one perfect representative of the nitpicking species. Nitpickers are part of any audience. They are easily distracted and annoyed by inconsistencies in your slides- and there always are inconsistencies such as misalignment, inconsistencies in font choice, size, colour, and style, inconsistencies in layout, spacing, spelling (spelling mistakes are very irritating), use of capital letters in titles, or inconsistent bullets. The nitpicker will even look at your clothes and nitpick on the way you dress, your choice of colours, etc… The nitpicker is by definition a neat and orderly person, with a particularly developed critical sense. Even if you are not, by any stretch of the imagination, a messy person, the nitpicker may find you “sloppy”, “careless”, or unskilled in design. If the nitpicker is your boss (or your spouse), you know what I mean.

Why are the nitpickers blessed? Because their talent is also a burden, to them and to others. Their highly developed critical eye is a curse. They have to repress their feelings because all that negativity in comments is not good for making friends. They need your gracious spirit. Given a chance to provide honest feedback, they will love you for letting them inspect your slides, particularly if you thank them profusely after their expert nitpicking feedback and take them out to dinner to show your appreciation. It does not matter how good you are, you will never beat the nitpicker at his/her game. And this is not a gender specific skill. Men and women are equally gifted.

The nitpickers are blessed because, without their honest feedback, your slides could be considered sloppy by some in your audience… including people who could influence your career. To them, sloppy slides points to the sloppy or junior researcher. Even if that deduction is far from the truth, you cannot afford to have people associate the two.

Therefore, when your presentation is prepared, and prior to delivering it in front of your audience, identify a nitpicker and ask for help in debugging your presentation to remove all pesky misalignments and inconsistencies. Your audience will be impressed by your care and attention to detail. But give credit where credit is due: always look to heaven to thank the blessed nitpicker 🙂

(Photo by VMOS, Flickr).

018Sequencing the scientific talk

What can you expect to accomplish in the typical 12-minute presentation one gives at a conference?  Does the expectation of the audience change during the course of a presentation? What do people expect at the start of your talk? Do they keep the same expectation throughout your talk? Be ready to be surprised by the answers to these questions. Our guest, Dr Leong Munkew is CTO and deputy CIO of  the Singapore National Library Board.

017Presenting patents and formulas

Strangely enough, knowing what is important in a patent presentation enables us

1) to bring light on an age-old question: Should one display formulas in a scientific talk?

2) to learn how to position our scientific contribution in the best possible light

Our guest, Dr Leong Munkew, was until recently CTO and deputy CIO of  the Singapore National Library Board.

What can the scientist who presents learn from Herbert Simon (Part 1)

Nobel Laureate Herbert Simon, in a 1969 article entitled “Designing Organizations for an Information-Rich World”, points out the problems created by the wealth of information.

A rabbit-rich world is a lettuce-poor world. […] Now, when we speak of an information-rich world, we may expect, analogically, that the wealth of information means a dearth of something else – a scarcity of whatever it is that information consumes. What information consumes is rather obvious: it consumes the attention of its recipients. Hence a wealth of information creates a poverty of attention, and a need to allocate that attention efficiently among the overabundance of information sources that might consume it.

Let’s step back from this world view, down to the ballroom where the scientist presents. The problems are similar. During a presentation both presenter and slides are competing for the attention of the audience. Attention, Herbert Simon points out, is not easy to divide.

Human beings are essentially serial, 0ne-thing-at-a-time devices. If they attend to one thing, they cannot simultaneously, attend to another.

Expecting the audience to discover alone how to connect what is heard with what is seen on an information-rich slide, is expecting far too much! Discovering which area on the slide is alluded to by the speech, requires much attention. Because attention, like the time it requires, is scarce, little attention is left for the later (and much more important)  stage of knowledge extraction from the message content. By the time the audience is ready to process the information, the presenter will often have shifted to a new area of interest. And the twain do not meet!

Matching what the eyes see with what the ears hear is not simple. It is not just a matter of helping the eye focus on the area being described (although it helps). The audience has to be familiar with the vocabulary and symbols used, and has to have prior domain knowledge before being able to match oral information with visual information. For example, display multiple colorful shapes on a screen, say a blue dodecagon, a red circle, and a green cone,  and ask the audience: focus on the polygonal shape with an infinite number of sides, and whose shape reflects light in the 620-670 nanometer range. The audience is presumed to have sufficient prior knowledge to identify the shape. But how learned is the audience? How much of the vocabulary used by the presenter is understood by the audience? And what is wrong with “look at the red circle”.

What can we learn from the time-bound antagonistic relationship between attention and information-rich slides?

1) Help the audience visually identify the object requiring people’s attention using the simplest possible vocabulary before you talk about this object, in order to minimize the demands on what will always be a limited attention pool.

2) Decrease the amount of information on a slide (by layering, pruning, or condensing) to a level that allows the audience to have more time to pay attention to what you say because it has less to look at, in a given amount of time.

3) Confine your oral comments to what is visually singled out –  To be matched, oral and visual information require co-location of attention. Synchronize the two. Do not digress.

By Jean-luc Lebrun

016Questions from experts and head hunters

Our new guest, Dr Leong Mun Kew, reveals what brings senior researchers to your talk. He even mentions the type of questions he would ask when head hunting for his lab. This insider view into presentation outcomes comes from the man who is now CTO and acting CIO of the Singapore National Library Board.

Robert Geroch suggestions applied to the subtitle of your talk

You will find Dr Geroch’s “suggestions for giving talks”, online. The paper is stored on, the open access site managed by Cornell University. I have read this excellent paper many times and recommend you do likewise. My intent is not to ask you to change the title of your  talk. As soon as your conference abstract or paper has been accepted, this title is pretty much carved in stone. It will bring the audience to you – and, justifiably, the audience expects the title of your talk to be the same as that featured in the conference program. A dull demagnetized title or a title replete with repealing highly technical keywords cannot be repaired post publication. Expect experts or sleepers to your talk. If, on the other hand, your title has centripetal appeal, if it is a centre of interest to experts and non experts alike, you can enhance its understanding and appeal, right there and then, on the title slide, by adding a subtitle that really makes your focus clear. A good subtitle is easily understood by ALL.

Dr Geroch writes

“Thus, for an audience of relativists, “Linearized Fields in a Kerr Background Metric” sounds technical, “Perturbations of the Kerr Solution” sounds dull, and “Black Holes are Stable” sounds good.”

Questions are often frowned upon by editors when used as titles, but they are always acceptable as subtitles on a title slide. “Can a mesocellular siliceous foam firmly entrap a catalytic enzyme?”, “what if we could actually firmly entrap a catalytic enzyme in a mesocellular siliceous foam?”  Notice that the expectations set by these two questions are different. The first question focuses the audience on the couple of words “firmly entrap” – a method -, while the second question prepares the audience to a presentation of the outcomes of firm catalytic enzyme entrapment.

Use the subtitle to guide audience expectations, but do not let that be an excuse to skip the presentation of the keywords that brought the audience to your talk in the first place.

By Jean-luc Lebrun

015 personal credibility

Not every piece of research represents a paradigm shift. How is one to present research which is lower on the innovative scale? In this podcast we also discovers that a polished abstract is not enough to bring an audience to your talk. Listen in as Professor Motiwalla shares his experience.

What can the scientist who presents learn from Santiago Ramon Y Cajal

By Jean-luc Lebrun

Santiago Ramon Y Cajal was a neurologist who shared with Golgi the nobel prize in 1906. In his excellent little book “Advice for a young investigator”, translated for MIT press by Neely and Larry Swanson, one finds some remarkable insights on the perfect scientist presenter host. In the preface to his second edition Cajal writes about scientists.

While not large, there is nevertheless a group of young enthusiasts who stay in constant communication about their ideas and feelings because of their love for science and desire to collaborate on the magnum opus of progress.

If I am to accept Cajal’s definition of true blue scientists, I cannot help but wonder where has the presenter’s enthusiasm gone? Where is the passion? Why let fear strap and padlock your passion in a straightjacket prior to delivering the scientific talk? Yes, the fear may be there, let it be. But then, be a Houdini presenter, deliver your passion, let its fire ignite interest in your work so that like-minded international colleagues from your audience desire to network with you. How do you do that? First and foremost, prior to climbing on the stage, recharge yourself with the excitement that ionized you when your working hypothesis was verified by your data. Then banish the thought of captivating minds with result outputs, because people do not celebrate outputs, they celebrate outcomes.

Nothing highlights the energetic personality of the investigator better, distinguishing him from the throng of automatons in science, than those discoveries where perseverance and logic get the upper hand over mechanics, where brain is paramount and material facilities are negligible.

Never miss a chance to present your current achievements in the context of your past work, to establish credibility through tenacity, to dazzle by the power and soundness of the thread of reasons sustaining your hypothesis, and to confound the big spenders with the frugality of your data needs because of the excellent representative and discrimination power of your data. Do not belittle or silence the story of your data if that story builds your credibility. Do not brush aside the history that led to your findings, if that history forged your expertise.

Microphones and how they make you sound

Video on microphones
Microphones – you love them because they extend the reach of your voice, and you hate them because they sometimes create problems: they whistle, they break down, they get in the way… Knowing how to handle them correctly and according to their varied abilities and models is a must for the presenter who wants to remain in control of how he or she sounds.