While most of us will be very familiar with this concept, Pryor continues on to provide a great review of the fundamentals with plenty of examples. Reminding ourselves of these basics should prove useful both for changing our own behaviours and helping our patients change theirs. She explains the importance of timing this reinforcement correctly – it can only provide information to the learner if it happens rapidly after the behaviour. Once a behaviour is learned it is best maintained over time by being reinforced only sometimes. We all tend to reinforce ourselves too late for our efforts (see later for the ingenious Tiny Habits solution for this), and it’s also not unusual to either attempt to reinforce ourselves all the time or (probably much more commonly) to neglect to ever reinforce ourselves for an already learned behaviour.

 Two further insights that stood out for me include the concept of behaviour chains and that of ‘prelearning dips and tantrums’. Behaviour chains are behaviours involving many known steps, and these long series of behaviours are of course very common in our daily existences. Seemingly counterintuitively, they should always be trained backwards. If we are working on, for example, memorising a piece of music or a speech, divide the task up into five sections, and memorise these from the reverse order, starting with the last. Pryor explains we will always be going from ‘…stuff you’re not quite sure of yet into the great, reinforcing, well-memorised stuff you know cold.’ Prelearning dips often occur when a behaviour is being brought under stimulus control (that is, trained to be evoked by a new stimulus) – the trainee suddenly stops not only responding to the stimulus, but responding altogether. Pryor believes this is due to a shift in awareness: the trainee has noticed the stimulus and becomes aware that this signal has something to do with whether it gets reinforced. At this point it attends to the signal rather than performing the behaviour so it is not reinforced. This may lead to a frustration she labels the ‘prelearning temper tantrum’. In humans, these tend to take place when longstanding beliefs are challenged and the subject knows deep inside that there is some truth in the new information. Realising that what has been learned is not quite true seems to lead to a furious comeback and to excessive response, something I’m willing to wager most of us have experienced on numerous occasions both from ourselves and others.

 Of course behavioural principles can also be used to remove undesirable behaviours, and there is an entire chapter covering eight methods for achieving this. Something I remember finding a major revelation way back when I was first studying psychology and I periodically need to remind myself of in life regards the use of punishment. Pryor wryly introduces punishment as ‘…humanity’s favourite method’ of behaviour change. For sound scientific reasons much of the time punishment doesn’t work at all, yet she laments, our typical response to this is simply to escalate the punishment rather than try one of the more effective strategies for behaviour change. Punishment does not coincide with the undesirable behaviour (which, of course, has usually been engaged in precisely because it has previously been reinforced, and again of course it usually has already been this time too), and as mentioned above, timing is everything if we hope for trainees to connect ‘B’ and ‘C’. Even if they are able to do so, the trainee is unable to mitigate the punishment in the present because they cannot change their actions in the past. Furthermore, and fundamentally, they learn nothing about how to change the behaviour. What they will learn, if the behaviour is so strongly motivated that they need to continue it, is to try not to get caught. Guilt and shame are self-inflicted punishments and of course similarly ineffective. I believe one of the best things we can do as practitioners, both in relation to individual patients and to society at large, is to use this information to discourage ourselves and others from engaging and supporting ineffective and harmful punitive measures. Fortunately, there are plenty of other much more effective options available to remove undesirable behaviours. Methods 5 through 8 Pryor describes as the ‘good fairies’ of behaviour change, and include training an incompatible behaviour, putting the behaviour on cue (then never giving the cue), reinforcing anything and everything that is not the undesired behaviour (‘shaping the absence’), and changing the motivation.

 Published some 35 years later, I’m confident BJ Fogg’s Tiny Habits will also become a classic work on the application of behavioural principles for enabling behaviour change. Fogg is the founder and director of the Behaviour Design Lab at Stanford and shares his practical solutions and discoveries from twenty years of research, many of which are fundamentally different from how behaviour has previously been approached. His first maxim is‘Help people do what they already want to do’, always a useful reminder for us as health professionals to let our patients set the agenda – while this patient-directed approach may at first glance seem foreign or overly new age, intriguingly, as we’ll discuss later it is liable to lead to them doing what we want them to do anyhow.

 There are two aspects covered in the book that I feel are quite revolutionary, and have certainly changed my practice. The first of these is the less obvious, and perhaps even counterintuitive idea that focussing on small actions that can be completed in less than 30 seconds (i.e. ‘tiny habits’) is an effective – potentially the most effective – method of enabling long term behaviour change success. Tiny habits require minimal time, emotional, and financial investment, along with being less reliant on motivation and willpower, so they enable people to get started immediately. Importantly, they are easy for people to succeed at and can grow into larger habits. Fogg’s Behaviour Model states that a behaviour will occur when three things come together at the same time: motivation, ability, and a prompt (B = MAP). He explains that motivation is unreliable and tends to vary greatly over time, which of course will be congruent with our own experience. We are therefore much more likely to create new habits and behaviours when we focus on altering ability and making the behaviour easier to do. He discusses how to do this in detail in the book, but also of course making habits ‘tiny’ makes them easier to perform – rather than starting out aiming to do 20 pushups for example, we might create a tiny habit of doing 2 pushups against a wall. No behaviour will happen without a prompt of course, and so he suggests using an existing routine or event that happens regularly to serve as a prompt for the new behaviour (e.g. ‘after I brush my teeth, I will do 2 pushups against the wall’).

 The next aspect seems a lot more obvious, but I believe no less revolutionary at least as far as my practice is concerned. Fogg explains that if nothing else, the reader should take away the idea that people change best by feeling good, not by feeling bad. His second maxim is ‘Help people feel successful’. Fogg recommends, in fact demands, that completion of a behaviour/tiny habit is followed immediately by a ‘celebration’. A celebration is described as something you do to create a positive feeling inside yourself – a feeling of success that Fogg believes is so important and lacks an appropriate term in the English language so he has created his own term – ‘shine’ to label it. Although to those of us who live outside of the at times delightfully unselfconscious land of the USA this may sound cringeworthy, I have to admit he seems to be onto something here. So give it a try yourself (perhaps when nobody’s looking at first) if you’re not convinced it works (I wasn’t) and see if you can come up with some of your own ‘celebrations’. There is a long list of suggestions in the book (100, in fact) ranging from giving yourself a double thumbs up, to complimenting yourself, to hearing a roaring crowd, to posing like Usain Bolt does after he wins a sprint. Fogg convincingly argues and demonstrates that it is emotions that create our habits, not repetition per se.

 Tiny Habits also provides a comprehensive approach to ‘untangling’ bad habits. Fogg explains that our unwanted habits can be thought of as a tangled rope that’s full of knots. You have to untangle the rope step by step instead, so he encourages analysing our unwanted habits and identifying their component parts or ‘knots’. He points out that general habits such as ‘eating too much junk food’ are made up of numerous specific behaviours, for example ‘buying my breakfast at the petrol station’ or ‘eating chips while I watch TV in the evening’. Once we have identified the ‘knots’, we start to untangle our unwanted habits simply by choosing the easiest knot to untangle first, then moving on to the next easiest in turn once the first knot has been unravelled. Fogg explains that the tougher knots can be dealt with when we have accrued experience and momentum, and that often you might not even need to address all the specific habits you identified in the first place because some of them will fall away on their own.

Hopefully reviewing these practical approaches and principles of behaviour change will have left you with some fresh ideas for helping your patients (and maybe even yourself) adopt healthy habits too. I have found keeping in mind the importance of positive reinforcement and the idea that it is our emotions that help (or hinder) us to adopt new habits very useful. Of course, you may have noticed that I have focussed strongly on behaviour change at the individual level. No doubt you can also appreciate that these principles apply to group behaviour and at the societal level too, and both Don’t Shoot the Dog and Tiny Habits also address this to some extent. While some may have concerns about the idea that we may have less (or even any) rational control over our behaviour than has been presumed, I personally find the elucidation of these behavioural principles to be at once both humbling and affirming. There are no longer ‘good’ people and ‘bad’ people, rather ‘good’ and ‘bad’ behaviours. Behavioural psychology encourages us to analyse the ‘bad’ behaviours, considering what might be reinforcing these, and to help slowly untangle them rather than blaming the individual. I find that looking through this lens we have a much more positive and compassionate outlook on others, and society in general. Large scale and creative application of these simple yet effective behavioural principles is essential for achieving the kinds of changes in humanity we require to tackle our current epidemics of chronic and infectious disease, along with the climate crisis.