Connections
Every dot is either a design concept or a structure in the brain. Every line is a dependency: the concept only works because that structure works. Choose any dot to see what it connects to.
Legend
Pick a dot on the map — or walk the list below, which carries the same thing.
The same connections, as a list
This list is not a summary of the map: it is the same data by another route. Each structure appears with the concepts that depend on it, and that is what the lines draw up there. Walking it from here, by keyboard, lights up the matching dot on the map. Next to each concept is what holds the link up: measured in the phenomenon itself, or a bridge of my own, when the structure was measured in another task.
hippocampus
The structure that turns recent experience into lasting memory. Everything your interface asks the person to remember tomorrow passes through it today.
Linked to amygdala, medial temporal cortex, long-term memory.
6 concepts
- Jakob’s law Break the pattern only when you can say why.
- Availability heuristic Fix the worst case before the average case: it is the vivid that stays in memory.
- Peak–end rule Invest in the high point and the ending; the middle is hardly remembered.
- Von Restorff effect One element different from the rest is remembered. Several different ones, none.
- Serial position effect What needs to be remembered goes at the beginning or the end of the list.
- Choice-supportive bias Confirm the choice, but leave the way back open.
V1
The first area of the brain, right at the back of the head, to receive what the eye sent. It is where the image becomes contrast, edge and orientation, before you recognise what you are looking at.
Linked to V2.
5 concepts
- Law of proximity What belongs to the same subject sits together; distance is already information.
- Law of similarity The same visual treatment means the same function, even if the elements are far from each other.
- Law of uniform connectedness An explicit line between two elements is usually enough, even against distance.
- Law of Prägnanz If the screen does not explain itself as a wireframe, colour is not going to fix it.
- Law of legibility Contrast, size and leading come before the choice of typeface.
prefrontal cortex
The 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.
Linked to medial prefrontal cortex, ventromedial prefrontal cortex, working memory, frontoparietal circuits.
5 concepts
- Cognitive load theory Add up everything the screen asks for at once, and take away half.
- Miller’s law Group into blocks of up to four, and make the blocks contrast with each other.
- Clustering illusion Before presenting a pattern in the data, look for what refutes it.
- Choice-supportive bias Confirm the choice, but leave the way back open.
- Flexibility and efficiency of use Offer the guided route and the shortcut, not a middle ground that serves neither.
ventromedial prefrontal cortex
It 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.
Linked to prefrontal cortex, orbitofrontal cortex, ventral striatum.
5 concepts
- Aesthetic–usability effect Do not refine the aesthetics before validating the concept, the finish hides the defect.
- Temporal discounting If the value takes time to appear, deliver pieces of it along the way.
- Jakob’s law Break the pattern only when you can say why.
- Scarcity bias Only show scarcity when it is true, and say what the limit is.
- Anchoring bias The first number becomes the ruler. Choose carefully which one you show first.
frontoparietal circuits
The pair that supports working memory: the prefrontal cortex holds the information active while the parietal lobe keeps track of where things are.
Linked to working memory, prefrontal cortex.
5 concepts
- Hick–Hyman law Cut what does not change the decision. Splitting into steps does not reduce the cost of choosing, it spreads it.
- Cognitive load theory Add up everything the screen asks for at once, and take away half.
- Miller’s law Group into blocks of up to four, and make the blocks contrast with each other.
- Salience bias Highlight one thing per screen. Two is already none.
- Flow state Raise the difficulty at the same speed the person improves.
ventral striatum
Part of the reward circuit that tallies gain and loss. It reacts more strongly to losing than to gaining the same amount — the asymmetry behind a good part of the decision biases in this catalogue.
Linked to ventromedial prefrontal cortex, basal ganglia.
5 concepts
- Aesthetic–usability effect Do not refine the aesthetics before validating the concept, the finish hides the defect.
- Temporal discounting If the value takes time to appear, deliver pieces of it along the way.
- Endowment effect Don’t take away what you have already given. If you must take it away, warn first and say what goes in its place.
- Social proof A real social number helps. An invented one destroys trust in the rest of the screen.
- Illusion of control Give real control along with the feeling of control.
V2
The area right after V1. It joins the edges V1 detected, separates figure from ground and decides which elements form a group, all of it before you notice you looked.
Linked to V1.
4 concepts
- Law of proximity What belongs to the same subject sits together; distance is already information.
- Law of common region A shared border or background can group even against distance.
- Law of uniform connectedness An explicit line between two elements is usually enough, even against distance.
- Law of Prägnanz If the screen does not explain itself as a wireframe, colour is not going to fix it.
medial temporal cortex
The inner part of the temporal lobe, hippocampus and surroundings, through which fact and episode pass to become lasting memory. Its role is temporary: over time the memory ends up stored in the cortex and stops depending on this region.
Linked to hippocampus, long-term memory.
4 concepts
- Law of visibility If it is essential, it is on screen. Hidden menus are for the secondary.
- Availability heuristic Fix the worst case before the average case: it is the vivid that stays in memory.
- Peak–end rule Invest in the high point and the ending; the middle is hardly remembered.
- Von Restorff effect One element different from the rest is remembered. Several different ones, none.
working memory
The 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.
Linked to prefrontal cortex, frontoparietal circuits, long-term memory.
3 concepts
long-term memory
What 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.
Linked to hippocampus, working memory, medial temporal cortex.
3 concepts
basal ganglia
Together with the cerebellum, they store what the body learned to do without thinking: typing, swiping, reaching an icon. It is the memory that survives distraction.
Linked to ventral striatum.
2 concepts
medial prefrontal cortex
The part of the prefrontal cortex that thinks about people: what others want, what they think of us, whether they can be trusted.
Linked to prefrontal cortex, mentalising network.
1 concept
orbitofrontal cortex
It 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.
Linked to ventromedial prefrontal cortex.
1 concept
amygdala
Two 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.
Linked to hippocampus.
1 concept
cerebellum
The structure low at the back of the skull that automates movement and sequence. The more someone uses your product, the more the operation migrates here, and the costlier it gets to change what has already become automatic.
1 concept
superior colliculus
A station in the brainstem that pulls the gaze towards what moves or contrasts, before the person decides to look. It is that reflex that every visual highlight hijacks.
1 concept
mentalising network
The circuit that infers what goes on in other people’s heads: intentions, beliefs, desires. It is what comes into play when the interface has people on the other side, in the rating, in the comment, in the count of those who have already bought.
Linked to medial prefrontal cortex.
1 concept