Subliminal Conditioning: Pavlov’s New Pet

While flying recently, I was handling the aircraft on an instrument approach in for a touch and go. I was wearing the oxygen mask, as we had practiced the smoke and fumes drill, and I hadn’t landed wearing the mask for a while. It was a good training opportunity, however in itself it provided a bit of a distraction. Additionally, the weather was quite poor, and the cloud base was close to the minima for the approach. On reflection, it was one of those approaches where the holes of the Swiss Cheese were lining up (Reason, 1990). Nonetheless, I felt within mild stretch, but not overloaded by pressure, so I was comfortable in continuing the approach.

As we descended, I missed my usual call of the RADALT (RADar ALTitude) which displays on the Primary Flight Display (PFD) at around 2500’. I missed the call, as the RADALT didn’t switch on. I continued the approach, oblivious to the missing height countdown and as I became visual with the runway lighting, I switched to a visual approach as we normally would.

Within the final hundred feet, I could sense something was slightly off. As the landing attitude became apparent, I realised I didn’t have the usual audible height callouts from the RADALT which were my usual cues for bringing the powers all the way back and starting the flare. This cue, I didn’t realise I had, until it wasn’t there. The landing was safe, albeit it slightly firm, and instantly I had realised why. I was conditioned to hearing the RADALT callouts and had associated the actions of retarding the power levers and flaring with these.

After the sortie and reflecting on this, it got me thinking about how many times I’d landed the aircraft without those callouts. The answer – never! During training, we were taught to land the aircraft based on visual cues, but over time I’d become acclimatised to hearing the callouts and began to associate those visual cues with audible ones.

The Human Behind the Decision Making

The human information processing system takes data from the world around us, prioritises it and decides upon an appropriate action. This happens sub-consciously, unless of course we decide to actively assign our attention resources to a particular activity. We take in this data through our senses, whether its touch, sight, sound, or one of the more obscure sensory channels such as proprioception (sensing your own body’s position and movements – it’s how you can touch your nose with your eyes closed).

Image from Wickens et al. (2013)

Let’s look again at what happened on the approach to land. Every flight up to that day was generating a subconscious feedback loop, which was embedding the aural stimulus into my long-term memory. While initially I was applying attention resources to the skill of landing, my brain began to associate the motor response with both visual and audio cues. The more I land, the more these cues are embedded, and the repetition stores the skill. Now when I land I apply less attention to the act as the behaviour is automatic; my attention can go onto managing a simulated emergency and the procedural instrument approach! As the time lands to activate the landing skill from my memory, my brain is waiting for the audio cues. They don’t come. It isn’t until the visual cues come into play, and I get the feeling ‘something isn’t normal’ that the motor response kicks in to flair, albeit marginally later than usual. The result – a slightly firmer than usual landing, but where else does subliminal conditioning creep in? Where could the impacts be worse?

Conditioned Behaviour: One Man and His Dog

So where does Pavlov sit in all this? You may have already heard of his famous experiment from the early 1900s. If not, go check it out! In short, he explored the psychological impact of applying a stimulus to subsequent action, to trigger a response in dogs. It was initially observed that dogs would salivate when they are given food; this was an unconditioned response to an unconditioned stimulus. He started to introduce a metronome (although it’s often referred to as a ‘bell’) just before the dogs received their food. The metronome alone generated no response in the dog’s salivation – why would it?! Over time, this repetition of the metronome coming with food, conditioned the dog to expect one with the other. Eventually, the dog would increase salivation upon just hearing the metronome – it had become a conditioned stimulus.

Credit: Simply Psychology

We see this conditioning around us all the time – not just when landing an aircraft! Advertisers use it to associate certain colours or music with a brand. If you saw a big, yellow M, with curved edges and no other context, you wouldn’t be thinking of Mitsubishi would you? And every time you hear Jess Glyne’s Hold My Hand, you don’t think about booking a holiday with easyJet. This subliminal (below our threshold of consciousness) conditioning is often harmless. But what about when it isn’t?

It is worth thinking about those everyday processes you do, and what responses are automatic. Many of us drive to and from work with little thought, but we learned the skill once upon a time! There may be certain sensory cues embedded within us that we are completely unaware of, and these may generate an unexpected action. While we can’t go inside our brains and see the list of stimuli and responses (but that would be really cool, wouldn’t it?!), we can try to bring our conscious into action a little more. Automatic behaviours are great and enable us to complete complex tasks. But awareness of our own cognitive limitations is crucial in accident prevention.