The figure comprises a black and white image of the brain, in which brain activity in response to cuing of an aversive or neutral stimulus is shown on a colour scale. There is a concentration of activity in the amygdalas. Below the brain image are two vertical bar charts showing the increase in activation in both the left and right amygdalas in a group of 14 participants with GAD and in a group of 12 control participants. The vertical axes are marked increase in activation of amygdala and are marked from zero to 0.4 at intervals of 0.2 arbitrary units. For both controls and participants with GAD, there was no difference in anticipatory amygdala activation between the groups that subsequently underwent aversive and neutral trials. But the increase in activation in the GAD groups was double that of the control groups (around 0.2 compared to 0.1 respectively).