The Affect Effect


Or why you may think that frying your brain with a mobile phone is good for you…

So, straw poll, without thinking about it are mobile phones good or bad? I’m betting your immediate answer was ‘good’. Now again as quickly as possible, do you think the radiation that your mobile emits could be a risk?

Now for extra points, WHY did YOU think that? You didn’t have any time to think about it so what formed your risk assessment?

The answer is at the heart of what’s called the affect heuristic, or how we perceive risk is often driven by our immediate emotional reaction (or affect) (1).  

Now mobile phones are a great example of this heuristic at work. Everyone loves their mobile phone because, it empowers us, has all these neat gadgets, is essential for our life among the digiterati, is a fashion accessory, peer group essential… you name it there are a host of reasons. But, mobiles also emit radiation and we collectively have a strong and persistent dread of radiation (2).

The Zero Affect: After this article, the west’s peception of radiation was changed for ever (Image Source: Daily Telegraph)

So how do we reconcile the two? The answer is simply that humans use how they feel about something as a rule of thumb to test its risk. So although we intellectually understand that mobile phones emit radiation we also feel that they are low risk because emotionally, ‘good = low risk’.

Now there are a lot of good reasons why such a heuristic, or rule of thumb, should exist, after all it’s a good guide to safe behaviour in well understood situations where we don’t have (or really need) much hard quantitative data, such as running away from a sabre tooth tiger.

The Peaceful Atom vs The Atomic Plague (Image Source: US AEC)

However such a heuristic does tend to breakdown and generate dubious responses when we deal with circumstances were a situation or technology presents both opportunity and peril or thinking about risk requires high end numeracy (3).

And? Well regardless of what findings the effects of exposure to mobile phone radiation we are unlikely to give up our mobiles. Simply put the head is rarely able to over rule the gut, at least not without a fight … :-).

More seriously when there is no direct ’emotive’ appeal of a new technology with some risk attached, public perception will skew towards ‘bad = risk’, one can prattle on about the peaceful atom all you like but…


1.  Affect may be more formally defined after Slovic (1999) as a positive (like) or negative (dislike) evaluative feeling toward an external stimulus (e.g. some hazard such as cigarette smoking).

1.  Ever since William Burchett’s  ‘Atomic Plague‘ article in the Daily Express 1945. While the consequences of the use of an atomic device on a population center are horrific in themselves it is instructive to consider how the use of the term ‘plague’ which has a an almost universal visceral response may have also had an effect on the ‘affect’ so to speak.

2.  Interestingly the affect has a greater effect when decisions are made under time pressure, an issue that should be seriously considered as part of any study of human error.


Slovic, Paul., Trust, emotion, sex, politics, and science: Surveying the risk-assessment battlefield. Risk Analysis, 19, 689-701, 1999.