Neuroscientists at the University of Amsterdam have uncovered a network of different brain regions involved in switching between quick and accurate decision-making. Their findings were published in the Journal of Neuroscience on 30 November 2011. The UvA researchers worked with colleagues from the University of Newcastle (Australia), University of Bergen (Norway) and the University of California (US).
Leendert van Maanen and his colleagues used a behavioural task to view how brains react to time pressure. The subjects had to perform a ‘moving dots task’ (popular in neuroscience and research with primates) in which they had to make decisions while being scanned by an MRI machine. In some cases, the tasks were performed under time pressure, in other cases not. During the task, their brain activity was measured.
Interaction between speed and accuracy
The researchers examined how flexible the subjects were when dealing with changing time constraints and which brain regions signal these changes. Using a mathematical model developed for this study, they showed that a region in the brain’s prefrontal lobe (the anterior cingulate cortex) plays an important role in decision-making under time constraint. This region of the brain was more active in subjects who were better able to switch between situations with or without time constraints.
There was also greater activity in another part of the subjects’ brains: the pre-supplementary motor area. This increased activity corresponded to impulsive decision-making. The subjects risked answering incorrectly in this case, but were faster. The anterior cingulate cortex and supplementary motor area are connected to the basal ganglia (a group of nerve centers that regulate the making of choices). The two regions indicate if the basal ganglia needs to place more or less focus on the speed of the decision.
The afore-mentioned brain areas have previously been associated with decision-making. Thanks to the mathematical model the researchers developed for this study, the role of the brain areas in the interaction between speed and accuracy has now been demonstrated. This interaction plays an important role in daily life. To ensure correct decision-making, it may be wise to think about it for a long time, but in some cases a quick decision is actually preferable. For example, if a football player takes too long to shoot, an opponent will intercept the ball, and if a predator takes too long to attack, its prey may have already disappeared.
L. van Maanen, S.D. Brown, T. Eichele, E.J. Wagenmakers, T.C. Ho, J.T. Serences, & B.U. Forstmann: ‘Neural correlates of trial-to-trial fluctuations in response caution’, in the Journal of Neuroscience, 30 November 2011.