 Other effects are somewhat more damaging for a pure spotlight view, although they also stop short of refuting it entirely. The more-than-merely-spatial complexity of the way in which attention is allocated has been nicely demonstrated in a series of experiments by Dwight Kravitz and Marlene Behrmann (Kravitz and Behrmann, 2011). The participants in these experiments have their attention cued by a brief stimulus that is presented at one end of a shape that is shown on a computer screen. This shape might be a simple rectangle, a rectangle with bulbous ends, or a more complex ‘H’ or ‘h’ shape. It is presented alongside another shape, which in some cases has the same shape and colour, and in other cases is different. The resulting allocation of attention is then probed by measuring the reaction times to stimuli that are presented on and near these objects. Kravitz and Behrmann find that all the different properties of their stimuli interact to determine the way in which attention is allocated to the screen on which those stimuli appear. Most strikingly of all, they find a difference in the allocation of attention between trials in which the shapes on the screen are an upper and a lower case ‘H’, and trials in which the shapes are an upper case H and number 4, even though this number 4 shape is exactly the same as the lower case h, but presented upside down. Such findings suggest that attention, even when triggered by a simple spatial cue, is not allocated merely on the basis of location, but also on the basis of shape, colour, and arbitrary learned meaning.