’Inattention blindness’ due to brain load

When we focus intently on one task, we often fail to see other things in plain sight - a phenomenon known as 'inattention blindness'. Scientists already know that performing a task involving high information load - a 'high load' task - reduces our visual cortex response to incoming stimuli. Now researchers from UCL have examined the brain mechanisms behind this, further explaining why our brain becomes 'blind' under high load. "Engaging attention on a high load task has a strong effect on the brain's response to the rest of the world," says Professor Nilli Lavie of the UCL Institute of Cognitive Neuroscience. "It reduces both the level and precision, or 'tuning', of neural response to anything else around us that is not part of the task. "These effects of load on neural response explain inattentional blindness. Although our environment hasn't changed, the change in our brain response under load leads to inability to perceive otherwise perfectly visible stimuli outside our focus of attention," she explains.