Cognitive load theory

The load the theory measures is that of 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 →, and this part is solid: keeping information active while operating on it depends on 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 → and the frontoparietal circuitsfrontoparietal circuitsThe pair that supports working memory: the prefrontal cortex holds the information active while the parietal lobe keeps track of where things are.See it in Memory →See in the glossary →, and the capacity is small enough to be the bottleneck for everything the screen asks the person to hold in their head while they work. Ten years after the 1988 article, Sweller and colleagues separated three sources of load — the intrinsic load of the task, the extraneous load imposed by the material and a third, which would build understanding — and it is the second that design controls. The third did not survive revision, and in 2010 Sweller himself stopped treating it as a separate source. Load is measured in time, errors and retained capacity. There is no measure of cognitive load in stress hormone or in any other hormone. The prefrontal cortex and the frontoparietal circuits come from working memory studies (BaddeleyAlan BaddeleyFormulated the model of working memory this site uses as its base, the phonological loop, the visuospatial sketchpad and the central executive.One reference in this work:2003Working memory: looking back and looking forwardSee on Wikipedia ↗See in the bibliography →, 2003), and their link to load theory is my own.

an eraa condition

Add up everything the screen asks for at once and take away half is the rule of thumb. It applies in four moves. Giving the content a hierarchy, so the person knows where to start; limiting what appears at once, so working memory does not overflow; moderating contrast, so emphasis keeps its value; and giving clear, respectful feedback, so an error does not cost a second reading. In a sign-up form, what actually weighs on working memory is what the person has to hold in their head, like the code that arrived by SMS while they leave the screen to fetch it. The visible fields cost reading and deciding, not memory space, so add up everything the screen asks for instead of counting how many fields fit into four.

• 95% of decisions happen in the unconscious.

  There is no primary source: it is attributed to a Harvard researcher who never published the figure in that form. The distinction between deliberate and automatic processing is real, but it does not come with a percentage. Whoever presents one is quoting marketing.

• The senses take in 11 million bits per second and consciousness processes only 40.

  The numbers come from a 1986 estimate of sensory channel capacity, not from a measurement of consciousness, and they became a slide without the caveat. They serve as a metaphor for saying that we filter a lot, and not as data to support a decision.