Stop context switching to stop leaking IQ and time

In a quiet lab, a researcher hands subjects a stack of word puzzles. Halfway through, she interrupts some of them and asks them to switch to a separate hiring task. A quick lexical test shows something odd, and consistent: those who switched carry residue from the first task into the second. Their attention is split, performance drops, and the feeling of being busy hides the loss. This is attention residue, and it’s everywhere in modern offices.

Now move to a real workplace. Alex spends the morning bouncing between email, slide edits, and a budgeting sheet. After lunch he wonders why his budget logic feels foggy. It’s not incompetence. It’s diluted focus. Each switch comes with a cognitive hangover, especially when the prior task was unfinished. Those partial loops keep tugging on the mind like a buzzing phone in a drawer.

The fix is not perfection, it’s batching. When Alex blocks 90 minutes for budgeting, closes his inbox, and aims to finish the cost model skeleton, his brain gets to live in one context. He writes assumptions once, applies them across tabs, and notices an error he missed all week. Later, with clear edges around his inbox windows, he processes mail faster because he’s not leaving a spreadsheet half‑built to answer a “quick question.”

Decades of research on task switching show that sequential juggling still incurs a penalty. The brain needs time to let go of one goal and load another. When work is sliced into tiny pieces, that load time accumulates into hours lost and quality lowered. Batching into longer, uninterrupted blocks reduces residue and preserves working memory for the thing that pays the bills: deep thinking.

Pick one important task and give it a 90 to 120 minute home on your calendar tomorrow. Before you start, shut email and chat, put your phone in another room, and set a timer. Decide exactly what you’ll finish in that sitting, like a model skeleton or a first draft outline. Then add two short inbox windows later in the day and activate a simple auto‑reply that tells people when you’ll respond. When the block ends, savor the finished sub‑goal and jot the next step so your mind can let go. Try it once and notice the lift.