Fig 1.
(a) Experimental Design. We used a word-picture verification task in which pictures of animals or manmade objects were identified as members of either these superordinate categories, or at a more specific level. (b) Trial Structure. Words and pictures were presented simultaneously and participants were asked to press a button with their left hand when the picture and word did not match. These mismatching trials requiring an overt response occurred on 30% of trials and were not included in the subsequent MEG analysis.
Fig 2.
3D rendered cortical representations showing significant activity above baseline across conditions, during 500 ms post-target onset in four frequency bands (15–25 Hz, 25–35 Hz and 35–50 Hz).
t-Maps are thresholded at p<0.01 (corrected). All the activations represent event related desynchronization. Significant event related desynchronization was only observed between 5–15 Hz in a region of the right fusiform gyrus that overlapped with the activity observed at 15-25Hz, at a reduced threshold (p = 0.05) and thus this frequency band was omitted from this figure, although all of the whole-brain maps can be accessed from Neurovault (http://neurovault.org/collections/1937/). Arrows indicate the locations selected for the VE analysis.
Fig 3.
Time-frequency plots for each cortical site (ATL, FG, and CS) are presented in each column.
(A) Main effect of specificity. (B) Main effect of category. In both (A) and (B), the first and second row report the percentage signal change in total power for each condition, relative to their passive periods. The third row shows differences between the two conditions. The black lines in the time-frequency plots indicate regions showing significant differences between the two conditions (p < .05). See text for details.
Fig 4.
Percentage signal change in total power for animal and manmade objects judgements at the specific level are reported in the first and the second row.
The third row shows differences between the two conditions. The black lines in the time-frequency plots indicate regions showing significant differences between the two conditions (p < .05). Each cortical site (ATL, FG, and CS) is presented in each column. See text for details.