The psychophysical potential of this effect has been demonstrated by numerous follow-up papers. Drivonikou et al. (this short form will refer to Drivonikou, Kay et al.,
2007) have shown the lateralization of the category effect in the data of Daoutis et al. (
2006). Moreover, they used a procedure of Franklin, Pilling, and Davies (
2005) that differed slightly from the one of Gilbert et al. They still found results that were consistent with the lateralized category effect. Further studies compared different language groups and found that the lateralized category effect appeared differentially at language-specific borders (Drivonikou, Davies, Franklin, & Taylor,
2007, Roberson et al.,
2008; Roberson & Pak,
2009). Zhou et al. (
2010) observed that participants could be trained to develop a lateralized category effect for artificial categories in as short a time as 3 h (see also Drivonikou, Clifford, Franklin, Özgen, & Davies,
2011). According to Franklin et al., the lateralization of the category effect switches during language acquisition from the right to the left visual field (Franklin, Drivonikou, Bevis et al.,
2008; Franklin, Drivonikou, Clifford et al.,
2008). Gilbert, Regier, Kay, and Ivry (
2008) have claimed a general validity of the lateralized category effect beyond the realm of color perception by showing that it also appears for the discrimination of outline shapes of cats and dogs. For the categorization of oriented bars, an opposite lateralization effect in terms of accuracy has been found (Franklin, Catherwood, Alvarez, & Axelsson,
2010). However, the lateralization was reversed for infants, i.e., for orientation categories the infants' lateralization corresponded to the one for color categories in adults. While these studies did find lateralization to the left or right hemisphere, others did not find any lateralization (Liu, Chen, Wang, Zhou, & Sun,
2008), and some did not even find a category effect for color (Brown et al.,
2009; Lindsey & Brown,
2009; Pinto, Kay, & Webster,
2010).