자동 조종 모드, 뇌
우리의 뇌에는 자동 조종 모드가 탑재되어 있다. 뿐만 아니라, 상황에 따라서는 이 자동 모드가 수동 모드보다 훨씬 더 일의 효율을 높여주고 있다.
최근의 연구 결과에 따르면, 뇌가 어떠한 일에 능숙해지면 뇌는 그 작업을 잠재 의식을 다루고 있는 디폴트 모드 네트워크(DMN)라고 하는 별도의 뇌 영역으로 이관한다. 이 연구에서 28명의 피험자들은 약간의 학습이 필요한 카드 게임을 하게 되었고, 과학자들은 이들의 뇌 활동을 모니터링했다.처음에는 과학자들의 예상대로 진행되었지만, 게임에 충분히 능숙해진 피험자들의 뇌 반응이 활동 영역에서 DMN영역으로 옮겨지게 되었다. 그 순간 피험자들의 반응은 더 빠르고 정확해졌다.
이러한 뇌의 기능은 악기를 연주할 때 쉽게 찾아볼 수 있다. 예를 들어, 악기를 다루는 사람들이 머릿속으로 악기를 어떻게 다루어야 하는지 하나 하나 생각하며 악기를 다루지는 않는다. 그냥 몸이 알아서 자동으로 옴직인다.
이러한 점은 우리들도 실생활에서 충분히 경험하고 있다. 예를 들면, 자동차의 문을 열거나 신발끈을 묶는 것과 같은 일을 할 때 우리의 뇌는 자동 모드로 돌아가고 있는 것이다. 그리고 이러한 뇌의 자동 모드는 더 복잡한 작업에서 발동될 때 더욱 효과가 높은 것으로 밝혀졌다.
Your autopilot mode is real - now we know how the brain does it
Ever realised you have driven yourself home but haven’t really been paying attention? Brain scans have revealed that when your mind wanders, it switches into “autopilot” mode, enabling you to carry on doing tasks quickly, accurately and without conscious thought.
Our autopilot mode seems to be run by a set of brain structures called the default mode network (DMN). It was discovered in the 1990s, when researchers noticed that people lying in brain scanners show patterns of brain activity even when they aren’t really doing anything. This research provided the first evidence that our brains are active even when we aren’t consciously putting our minds to work.
But what does the DMN do? Several studies have found that it seems to be involved in assessing past events and planning for the future. Others suggest the network is involved in self-awareness – although this has been called into question by findings that rats and newborns appear to have a version of the DMN too.
It is unlikely that rats are conscious of themselves in the same way that humans are, says Deniz Vatansever at the University of York, UK. Instead, the DMN must have a more basic function, common to all animals. Vatansever and his colleagues at the University of Cambridge wondered if the network might help us do things without paying much attention, such as tying our shoelaces, or driving along a familiar road.
To investigate, the researchers asked 28 volunteers to learn a card game while lying in an fMRI brain scanner. In the game, each person was presented with four cards. They were then given a fifth, and asked to match it to one of the four.
But participants were not told the rules – they didn’t know whether to match the cards by colour or shape, for example. Through trial and error, each person figured it out after a few rounds.
While this happened, their brain activity resembled patterns that are typical of learning minds. But as the game continued, and the participants knew how to match the cards without much thinking, their brain activity resembled those of using the DMN – and their responses became faster and more accurate.
This suggests that when we “switch off”, our brains go into an autopilot mode that allows us to perform tasks reasonably without thinking much about them.
This might also help explain why some tasks – such as playing a well-known tune on a musical instrument – suddenly seem much more difficult when you go from doing them absent-mindedly to consciously thinking about them.
Boost your autopilot
In the experiment, people whose DMN structures are more strongly connected also performed better in the card game. In these people, the various regions fired together more consistently, showing more coordinated activity. This suggests that the more strongly a person’s DMN is linked up, the more effective their autopilot mode, says Vatansever.
It may be possible to train yourself to have a better autopilot mode. In other studies, people have been able to control their brain activity when shown real-time scans of their brains. Similar “neurofeedback” training may enable people to boost their brain’s autopilot mode, allowing them to perform better on tasks without directly focusing on them, says Paul Stillman at Ohio State University.