Emotion

Don NormanNormanWrote the book that gave affordance its name in design and formulated the three levels of emotional processing the site uses.One reference in this work:2013The design of everyday thingsSee in the bibliography → described our reactions to colours, shapes and sounds as happening at three levels: the visceral, which is the immediate, instinctive reaction; the behavioural, which is how we use and navigate; and the reflective, which is what we think about the experience afterwards. It’s at the visceral level that emotion enters first, with the participation of the amygdalaamygdalaTwo small structures in the temporal lobe that decide, in milliseconds, whether something is a threat or an opportunity. They respond to your screen before any conscious judgement about it.See it in Emotion →See in the glossary →, a small structure in the temporal lobe, and that’s why your screen meets this level before any other.

When we see a vibrant colour that recalls a ripe fruit, notice a suspicious shape or hear an unexpected sound, the amygdala sends signals to the brainstembrainstemThe oldest part of the brain, at the junction with the spinal cord. It handles what is non-negotiable — breathing, waking, reacting to a fright — and it is where almost all the signals from the senses pass through.See it in Senses and attention →See in the glossary → and prepares the defence response. This pathway is fast: it happens in milliseconds, well before the prefrontal cortexprefrontal cortexThe region behind the forehead, where the person decides, plans and sustains attention. It keeps one thing in focus at a time and inhibits the rest: it is where the bottleneck of conscious decision usually tightens.See it in Memory →See in the glossary → formulates any rational judgement. Defence isn’t the only thing that happens fast, and when the screen promises reward it’s another circuit that comes in, the mesolimbic dopaminergicdopamineThe chemical signal of reward and anticipation. It is not the molecule of pleasure, but of “worth seeking”, which is why expectation usually pulls more behaviour than delivery does.See it in Emotion →See in the glossary → circuit, which PankseppJaak PankseppMapped the basic emotional systems humans share with other mammals, including the seeking circuit.One reference in this work:1998Affective neuroscienceSee on Wikipedia ↗See in the bibliography → described in 1998 as a system of its own, the seeking system. They are two distinct circuits, and neither of them is an emotional brain fighting a rational one. What this demands of whoever designs is to care for the first instant of the screen, because that is what conscious judgement will confirm or deny.

On the other side of the same pathway is cortisolcortisolThe stress hormone, and a slow hormone: it takes twenty to forty minutes to peak, so it is not what explains the irritation with a frozen screen, but rather what builds up over a whole day of bad work. Sustained, it brings down working memory.See it in Emotion →See in the glossary →, the hormone the body releases under stress. It’s slow, taking tens of minutes to reach its peak, so it isn’t what explains the irritation with a screen that froze. What it explains is the accumulation, a whole day of waits with no reply, decisions that don’t close and badly explained errors, and sustained cortisol interferes with the hippocampushippocampusThe structure that turns recent experience into lasting memory. Everything your interface asks the person to remember tomorrow passes through it today.See it in Memory →See in the glossary → and the prefrontal cortex, leaving less working memoryworking memoryThe mental space where the person holds what they are using right now. It holds about four things, and they fade in seconds if they are not used.See it in Memory →See in the glossary → available for the rest of the day. There’s a name for this going around, “emotional hijacking”, popularised by Daniel Goleman, and it’s better not to use it. The name suggests an emotional brain taking the wheel from a rational brain, and that isn’t what happens. There aren’t two drivers, there is one whole system operating with less slack.

Any affective reaction can be described by two dimensions, valence, which runs from pleasure to displeasure, and arousal, which measures intensity, in the circumplex model RussellRussellFormulated the circumplex model of affect: valence and arousal as the two dimensions that describe any emotional state.2 references in this work:1980A circumplex model of affect2003Core affect and the psychological construction of emotionSee in the bibliography → proposed in 1980 and reformulated as core affect in 2003. This model is usually cited the opposite way from what its author defends. Russell is one of the founders of the psychological construction of emotion, and his argument is that an emotional episode is assembled each time, not triggered by a circuit dedicated to “fear” or to “joy”. The two dimensions are the raw material of the emotional episode, not the mark of a circuit dedicated to it. In design, they determine how urgent, attractive or uncomfortable an element is. A flashing red button generates high arousal and calls immediate attention at the visceral level, but without care it triggers discomfort, negative valence; a gentle micro-animation on click conveys success, positive valence, and moves on to the behavioural level, encouraging the action to be repeated.

As soon as the amygdalaamygdalaTwo small structures in the temporal lobe that decide, in milliseconds, whether something is a threat or an opportunity. They respond to your screen before any conscious judgement about it.See it in Emotion →See in the glossary → activates, it interacts with the hippocampushippocampusThe structure that turns recent experience into lasting memory. Everything your interface asks the person to remember tomorrow passes through it today.See it in Memory →See in the glossary → to prioritise emotionally charged memories, in the modulation McGaughMcGaughShowed how the amygdala modulates the consolidation of memories of emotionally intense events.One reference in this work:2004The amygdala modulates the consolidation of memories of emotionally arousing experiencesSee in the bibliography → mapped in 2004. A neutral event tends to fade in hours or days; an experience marked by fear, surprise or pleasure has a much better chance of getting through consolidation and settling in the cortex as a lasting memorylong-term memoryWhat the person still knows tomorrow of what they saw today. It does not live in one place only: it forms through the hippocampus and, over time, comes to live spread across the cortex.See it in Memory →See in the glossary →. At the reflective level, those memories form the opinion about the product, “this site made me feel safe”, “that app made me anxious”, and they are what decide returns and recommendations.

Although the amygdalaamygdalaTwo small structures in the temporal lobe that decide, in milliseconds, whether something is a threat or an opportunity. They respond to your screen before any conscious judgement about it.See it in Emotion →See in the glossary → reacts fast, the prefrontal cortexprefrontal cortexThe region behind the forehead, where the person decides, plans and sustains attention. It keeps one thing in focus at a time and inhibits the rest: it is where the bottleneck of conscious decision usually tightens.See it in Memory →See in the glossary →, especially the orbitofrontalorbitofrontal cortexIt sits right behind the eyes and assigns value: whether the thing is worth it, whether it is pleasant, how much it costs in effort. It answers before the person knows they asked.See it in Emotion →See in the glossary → and ventromedialventromedial prefrontal cortexIt makes the global judgement, the final opinion on an entire experience, not on each moment of it. It is because of it that the person sums up a ten-screen flow in a single sentence.See it in Emotion →See in the glossary → areas, comes into play right after to assess the context and moderate the intensity of the response. At this behavioural level, the person doesn’t just feel an impulse: they think “should I click?”, “is this alert trustworthy?”. A successful design harmonises the three layers, immediate attraction, clear functionality and positive reflection. That brake works with what the screen gives it to reappraise, and that’s why an alert that says what is at stake has a chance of being heeded, while one that only flashes becomes noise.