AMA #11: Improve Task Switching & Productivity and Reduce Brain Fog

Andrew Huberman, who introduces himself as a professor of neurobiology and ophthalmology at Stanford School of Medicine, opens this Ask Me Anything episode by explaining its context. It belongs to the premium subscriber channel, which he says was started to support the standard Huberman Lab podcast, released every Monday at no cost on YouTube, Apple, Spotify and other feeds, and to fund research on human beings in mental health, physical health and performance at Stanford and elsewhere.

He adds that the Tiny Foundation has agreed to match every dollar the premium channel generates for research studies, which he says doubles the total funding going to those studies. He then moves to the first listener question: is there a way to get better at task switching?

Huberman calls task switching something that "plagues many people," and says it is often confused with cognitive flexibility. To separate the two, he starts with the prefrontal cortex. He stresses that it is not a single area but "fairly varied real estate" with many subdivisions involved in cognition, directing action and withholding action. One of its main functions, when it works well, is letting us direct focus and thinking "in a context-dependent way."

His illustration is a school day. Math, history and social studies each demand different cognitive operations, yet some rules apply to all of them, such as sitting in a chair. Other rules apply only to one subject. Still others depend on the teacher rather than the topic: one teacher might let students put their feet up on the chair in front, while another might forbid it. In his telling, the prefrontal cortex, working with other brain areas, makes sure behavior, thinking and understanding fit the specific context.

Cognitive flexibility, he says, is the ability to switch types of cognitive operations depending on what you are trying to learn or understand. Task switching is related but different. He admits this is a simplified version and says both topics could fill their own full episodes.

First of all, task switching requires cognitive flexibility, but they are not the same thing.

He then explains how the scientific literature usually studies task switching. Participants perform one mental or physical operation, then switch to a completely different task, either at random intervals or at set ones such as every 10 minutes. A typical cognitive version has people count upward as high as they can in a fixed time, in steps of seven, or in steps of 7 plus 1 and then 7 minus 1, making it progressively harder. A tone or signal from the experimenter then tells them to switch to a different cognitive task. Another common design uses manual tasks, such as placing puzzle pieces, with switches to a different manual task. He notes that fewer experiments, "not zero, but fewer," have looked at switching between physical and cognitive tasks.

For an extreme example he describes chess-boxing, which he says really exists. Two people sit at a table in a ring and play chess for a set period. When a buzzer sounds, the table and chairs are cleared and they box for a round of perhaps one to three minutes, then go back to chess. He says twice that he is not recommending anyone try it.

He then describes his own struggle with task switching. Like everyone, he says, he needs some time to settle into a book chapter or a workout, but once engaged he becomes very focused. Getting out of that mode and onto the next thing is much harder for him, and he names this as one reason he often runs late: he is still mentally or physically caught up in what he was doing before. He calls it "something I'm constantly working on," and says this is why he has looked for and used tools to improve. He offers a few here and promises a full-length episode on the mechanisms and a longer list of tools.

Huberman's central recommendation is to introduce short transition gaps between the activities you are switching between. He says this is "nicely supported, both at the mechanistic level and at the practical level within the published literature," though he does not cite specific studies in this section. In his opinion the idea gets too little attention, and as a result many people place "an undue burden on themselves."

His main example is reading. Many people think they should focus on a book chapter immediately, without their mind flitting about. Huberman says that unless you are enthralled from the first word or intensely curious about the material, it will take about 5 or 10 minutes for the neural circuits needed to understand, digest and remember it to reach the activity levels you would experience as intense or even mild focus. He explains this with what he calls a push-pull in brain activity: moving to a new task requires engaging some circuits and disengaging others. That disengagement can be inhibition, or simply a fading of activity, "like a dimming of the lights in a particular room."

From this he concludes that you should not expect to drop immediately into "a narrow trench of focus" for anything you are not already highly skilled at or very interested in. He thinks the ramp-up is overlooked because some situations do grab attention instantly: watching the dot-dot-dot of an incoming text you care about, or waiting for directions from someone you cannot find in a big city. Those cases, he says, give a misleading standard for ordinary work such as reading unfamiliar material, working on a spreadsheet or taxes, or starting a conversation.

expect a 5- to 10-minute transition period.

He adds a clinical caveat. Many people wrongly conclude they have attention problems, though some may indeed have clinically diagnosable ADHD or another attention disorder, which he says he "certainly can't rule out based on this conversation alone." The same point applies to physical tasks. Expecting peak cycling or lifting with no warmup, or expecting to instantly forget a difficult or great conversation on the way in, is in his words "completely unfair" and "doesn't match at all the way that your neural circuits work." His first point, then, is to match your expectations to the underlying biology.