“…An important piece of evidence in favor of it is that the directions in stimulus space that become perceptually differentiated after categorization can be arbitrarily chosen by the experimenter (Folstein et al, 2012b;Goldstone & Steyvers, 2001a). Dimension creation would also explain why the effects of categorization training can be measured using orthogonal tasks, both through psychophysics (e.g., Folstein et al, 2012b;Goldstone & Steyvers, 2001a;Soto et al, 2017) and neuroimaging (Brants et al, 2016;Folstein et al, 2013), and why in the latter case effects are observed in high-level visual cortex. An alternative interpretation, which has received less attention in the literature, is that categorization training produces alterations in already-existing visual representations, simply enhancing the pre-learning selectivity of populations of neurons that happened to provide useful information for the categorization task (Brants et al, 2016).…”