Adaptive Behaviour Research Group, Department of Psychology, University of Sheffield, Sheffield, United Kingdom. m.d.humphries@shef.ac.uk|Adaptive Behaviour Research Group, Department of Psychology, University of Sheffield, Sheffield, United Kingdom. m.d.humphries@shef.ac.uk|Adaptive Behaviour Research Group, Department of Psychology, University of Sheffield, Sheffield, United Kingdom. m.d.humphries@shef.ac.uk