Imagine waking up thirsty at night and having to reach for a glass of water in the dark. Without a clear view, your brain has to estimate where the glass is and where your hand is—a challenge that often leads to imprecise movements. The brain processes two key pieces of information: It needs to know where the hand is and where to move it. But what happens if this information is inaccurate?
Scientists from the Sensorimotor Research Group at the DPZ have investigated this problem of visual uncertainty during movement control in a study with rhesus monkeys. The research is published in the journal Nature Communications.
In the experiment, the monkeys moved a cursor on a screen by hand, using a kind of joystick. Two types of uncertainty were investigated. In target uncertainty, the target of the movement was represented by several scattered objects, so that it remained unclear where exactly the target was located. In the case of feedback uncertainty, the cursor was replaced by several scattered, small objects so that it remained unclear exactly where the user’s own hand was located.