How focus works in the brain
Interactive explainer: the three attention networks, the ~4-chunk working-memory limit, and why interruption recovery is a range, not 23 minutes.
Productivity Signal
How attention, fatigue and memory really work
Systematic reviews first, single studies second, anecdotes never. Each explainer carries an evidence grade, names the popular exaggerations of its topic, and links to the planner that applies it.
Guides and analyses
The cost of context switching
Set switches per hour and task complexity to see switch costs and resumption lags add up over a day, batched vs interleaved. Illustrative, evidence graded.
Your brain on AI
Conceptual interactive model of delegate–generate–verify–integrate, plus the evidence on cognitive offloading, automation bias and the jagged frontier.
Brain fog at work: what it is, what causes it and what actually helps
Brain fog is a symptom, not a diagnosis. Documented causes ranked by evidence (sleep, stress, long COVID, thyroid, iron), what helps, when to see a doctor.
Burnout symptoms: how to recognise them and what the evidence says helps
Burnout symptoms by the WHO definition and three dimensions, validated self-checks, what the intervention meta-analyses show, and your legal rights.
Chronotype: how to find yours and plan deep work around it
Chronotype explained with the MCTQ and MEQ, how performance varies across the day, social jetlag, the 90-minute ultradian claim graded, and a plan.
Cognitive load at work: why your tools feel heavy and how to lighten them
Cognitive load theory applied to knowledge work: working memory limits, three load types, how tools and AI add load, and a 10-minute audit of your setup.
The cost of context switching: what the research measured
Switch costs, attention residue and the famous 23 minutes: what the studies measured, what got exaggerated, and a calculator for your own switching cost.
Decision fatigue, explained after the replication crisis
Decision fatigue and ego depletion after the replication crisis: the parole study, the failed multi-site replications, and what still works for your day.
Flow state: the conditions that work and the claims that do not
Flow state defined, the flow-performance evidence graded as correlational or causal, the conditions that precede it, and why most flow hacks lack support.
How to improve deep work (what the data says, not just the book)
Deep work beyond the book: how much focused time knowledge workers really get, the interruption data, four scheduling philosophies and a weekly plan.
How to reduce screen time and digital distractions (what actually has evidence)
Screen time, phone addiction and dopamine detox examined: what studies on phone presence and social media breaks found, and which changes measurably help.
How to stop procrastinating: what the meta-analyses say works
Procrastination is mood repair, not laziness. The meta-analyses, implementation intentions with effect sizes, interventions graded, a plan for one task.
Productivity and sleep: the evidence, without the hustle myths
Meta-analyses on sleep loss and cognition, the economic estimates, chronic restriction you stop noticing, and what to do when you cannot sleep more.
How to focus better: what the science of attention really says
What attention research supports: interruption costs, the 47-second screen attention baseline, what training does and does not do, and six graded tactics.
Related tools
Focus & Cognitive Performance Planner
Plan deep-work blocks around your meetings and energy, get a focus timer, interruption fixes and three experiments. Evidence-graded, no sign-up.
Newsletter
The Daily Signal
One topic a day from work, focus and AI, researched each morning and sent at about 8:30 Prague time, with its sources. No hype, one-click unsubscribe.