A University of Zurich team found that they can inhibit our impulse control and ability to opt for delayed gratification by disrupting activity in a specific region of the brain. Called the temporoparietal junction, this structure lets us take on the perspective of others — including that of the future self.

Image credits Philip Bump / Flickr.

Ahh, delayed gratification. That anathema of gamers everywhere.

The term refers to someone’s ability to put off a reward until later if it means getting a bigger cash-out. Imagine you can either take a wad of cash now or receive a much larger pile in a few weeks’ time. Which one do you choose? One of the most important factors determining that choice is your level of self-control — which, researchers have found, may be tied to your brain’s ability to take on another person’s perspective, such as that of your future self.

UZ researchers studied the link between a brain region known as the temporoparietal junction (TPJ) and this ability. In a new paper, they report that when noninvasive brain stimulation methods were applied to the TPJ, participants appeared less able to take on another person’s or their future selves’ point of view. They were less likely to share money with others, and much more likely to opt for an immediate reward than wait for a larger sum later on.

Linking the parietal and temporal lobes together, the TPJ plays a crucial role in social functioning. It’s known to underpin our ability to understand situations from other people’s perspective, but according to Alexander Soutschek, an economist at the University of Zurich and lead author on the study, it has been largely overlooked in previous studies on self-control and delayed gratification — which usually focus on the prefrontal region.

Buzzing “now” and “me” to the forefront

“When you have a closer look at the literature, you sometimes find in the neuroimaging data that the TPJ is also active during delay of gratification,” he said, “but it’s never interpreted.”

Each participant had a small magnetic coil attached to their skull for 40 seconds, during which it produced small electric currents in their brain to inhibit the TJP — a technique known as disruptive transcranial magnetic stimulation (dTMS). To rule out a placebo effect, a control group received TMS in another area of the brain.

Both groups then spent 30 minutes completing several tasks. In one of them, they were asked to choose between a reward ranging between 75 to 155 Swiss francs for themselves, or one shared between themselves and another person — either someone close to them or a complete stranger. For the second task, they were offered a choice between zero to 160 Swiss francs now, or a guaranteed 160 Swiss francs three to eighteen months later. The final task had subjects attempt to take on the perspective of an avatar and count the number of red dots on a ball that it could see.

Participants who had their TPJ inhibited were less likely to share money, and much more willing to take money up-front than delay gratification for the larger sum. They were also less able to take on the perspective of the avatar.

“The function of perspective-taking is essential to both of these tasks,” says Christian Ruff, a co-author of the paper and an economist at the University of Zurich,  both as “thinking how someone else would feel if you give them money and also how you yourself in the future would feel with that money.”

The findings suggest that this brain area plays a fundamental role in perspective-taking, a “very basic social mechanism” according to Ruff. This means the TPJ is essential not only for helping us figure what others may be thinking or feeling in social contexts (a principal part of emphatic behavior) but also in exercising self-control (as it allows us to understand what our future self wants and needs).

The team says that while their study focused on fundamental science, the findings could have enormous implications for people struggling with self-control, such as addiction. Ruff says that in addition to traditional procedures which aim to improve impulse control, it may be helpful to teach people to consider the perspectives of their future selves to help change their behavior.

“When people think about addiction, it’s often seen as a deficit in impulse control,” Ruff says. “Our results suggest that this other process is also very important—that the afflicted individuals may not be able to take the perspective of their future selves [who have not taken] the drug.”

But, even beyond battling addiction, our level of self-control and our ability to delay gratification play a part in almost every decision we take, from studying, eating healthy and exercising, to saving up for old age — which is why Ruff believes understanding them is key to improving our health and happiness.

The team’s paper titled “Brain stimulation reveals crucial role of overcoming self-centeredness in self-control” has been published in the journal Science Advances.