How to read the numbers: Today’s average = common in today’s population – not a target or optimum · Risk = what to watch out for · How-to = a practical step or time frame
Today’s average
The claim of an eight-second attention span is widely quoted but lacks a solid scientific source; what is clear is that we switch attention very often when working with screens. Working in single-task blocks with tabs closed and notifications off helps.
The mind wanders
A large study using smartphone experience sampling found that the mind wanders almost half of waking time, and people are on average less happy when it does. Try noticing during the day where your mind has drifted and gently bring it back – short meditation helps too.
Natural focus cycle
Ultradian rhythms are recurring cycles of activity and rest, well documented mainly during sleep; evidence for waking hours is weaker, but they are a useful working framework. Try focused work blocks of up to about 90 minutes, each followed by a short movement break.
Attention is governed primarily by the prefrontal cortex (PFC) — the region of the brain responsible for executive functions, inhibiting distraction and maintaining goals. The PFC is metabolically demanding and sensitive to stress, cortisol, sleep deprivation and dopamine dysregulation. That is why focus is the first thing to go under chronic stress.
When we have no specific task, the Default Mode Network (DMN) switches on — a brain network associated with “mind wandering”, self-referential thinking and planning. A healthy brain switches flexibly between the DMN and the Task Positive Network (TPN). Chronic stress and smartphone addiction undermine this flexibility.
The neurology of attention
Focus exists in two modes: top-down (voluntary attention — consciously directed, frontal cortex) and bottom-up (reflexive attention — the salience network, sounds, movement, notifications). The problem: notifications constantly activate the bottom-up system and interrupt top-down focus. After each interruption, it takes 23 minutes for the brain to return to a state of deep concentration (Gloria Mark, UCI).
What destroys focus
Multitasking — it does not exist. The brain switches between tasks (task-switching), generating “attention residue” with every transition. Chronic stress — cortisol directly damages the PFC. Sleep deficit — 17 hours without sleep = cognitive performance equivalent to 0.5‰ blood alcohol. Digital stimulation — every like and every scroll activates the dopamine system. Inflammation — neuroinflammation reduces attentional capacity. Nutritional deficiencies — omega-3, zinc, magnesium, vitamin B12.
The ultradian rhythm — working with your biology
The body (and the brain) works in 90-minute cycles (the ultradian rhythm). Each 90-minute block is followed by a 20-minute recovery phase — a dip in energy, distractibility. Most people suppress this phase with caffeine. Respecting the rhythm: 90 min of deep work → 20 min break (no smartphone) → the next block. A maximum of 4–5 blocks a day.
A protocol for deep focus
Morning: no phone for 60–90 minutes after waking (cortisol peak = naturally the highest focus). Batching: grouping similar tasks into blocks (emails twice a day, not constantly). Pomodoro+: 90 min of focus, 20 min break. Deep work environment: notifications off, a single tab, headphones with white/brown noise or binaural beats (40 Hz gamma for focus). Physical activity: a 20-minute walk before cognitive work improves focus by 20% (Harvard studies). Sleep 7–9 hours — the prefrontal cortex recovers exclusively during sleep.
