You know that feeling when you walk into a room and immediately forget why you came in? On your way there, you were thinking about grabbing your keys. But once you arrive, they've completely disappeared from your mind.

This is the "doorway effect," and according to new research, it reveals something profound about the nature of consciousness itself. When information is removed from working memory, it immediately seems to leave conscious awareness — suggesting the two may be deeply intertwined.

In a new essay in Scientific American, philosopher Henry Taylor of the University of Birmingham explores the complex relationship between working memory and consciousness, drawing on his forthcoming book on the subject.

Working memory is paradoxically both rich and poor. It draws information from sensory channels — vision, touch, smell — as well as from long-term memory and the brain's language processing systems. A "central executive" system coordinates these inputs, assigning tasks and keeping everything under control. Yet despite this wealth of access, working memory can only hold a tiny amount of information at any one time — roughly three to four items, as demonstrated in classic change-detection experiments.

The doorway effect illustrates just how fragile this system is. Walking through a physical threshold — a change in environment — can be enough to dump working memory and with it, conscious awareness of what you were just thinking about.

The emerging view among neuroscientists and philosophers is that working memory isn't just a storage system — it may be the very mechanism that gives rise to conscious experience. As Taylor notes, when information enters working memory, we become conscious of it. When it leaves, consciousness of that information vanishes. The relationship may not be coincidental.

Sources: Scientific American