In 117 out of 178 adult ROIs (14 ROIs × 13 subjects – 4 ROIs without tool or animal picture-selective voxels), the category preference for words corresponded with the local preference for tool or animal pictures. A sign test revealed that the probability of observing this proportion by chance is p < 0.0001. We therefore LBH589 concentration concluded that the category-selective response patterns for tools and animals in the adult brain were consistent across
stimulus format. In contrast, in both groups of children, the proportion of ROIs with a corresponding category preference words and pictures was at chance level (9- to 10-year-olds: 64 out of 134 ROIs: p = 0.33, 7- to 8-year-olds: 72 out of 144 ROIs: p = 0.53), so, in both younger and older children, selleck inhibitor the local category preference for words and pictures was unrelated. Chi-square tests showed
that adults had significantly higher proportions of areas with picture-like activations for words than the youngest and oldest group of children (overall age difference: χ2 = 12.56, df = 2, p = 0.002; adults vs 9- to 10-year-olds: χ2 = 10.134, df = 1, p = 0.001, adults vs 7- to 8-year-olds: χ2 = 8.13, df = 1, p = 0.004, 9- to 10-year-olds vs 7- to 8-year olds: χ2 = 1.39, df = 1, p = 0.71). We used Chi-square tests rather than ANOVA’s for this age comparison because the measure (whether ROIs show a corresponding category preference for words and for pictures or not)
is categorical. In general, both examined BOLD-related confounds were higher in children than in adults. To test whether between-group differences in BOLD-related confounds could explain the absence of sensorimotor activations for words in children, Clomifene we compared the consistency of category preferences across stimulus format in subgroups of 9 adults and 9 children matched on these confounds (see Section 2 and Appendix B, Table 1). Confound-matched adults showed significantly more areas with a corresponding category preference for words and pictures than confound-matched children (χ2 = 5.54, df = 1, p = 0.019). Moreover, sign tests revealed that the number of areas with a corresponding preference for tool or animal words and pictures was higher than chance-level in adults (p < 0.001) but not in children with similar levels of BOLD confounds (p = 0.235). Thus, the absence of sensorimotor activation when children read familiar words, was not due to BOLD-related confounds. Embodiment theories and research supporting these theories for adults, suggest that printed word meaning is at least partially represented in cortical regions that also process sensorimotor properties of the object categories described by these words (Barsalou, 2008, Fischer and Zwaan, 2008 and Pulvermueller, 2013). During reading training, children learn to extract semantic information from abstract words shapes.