Figure 4. The impact of head orientation and facial expression on the fMRI signal in the both-repeated condition. a, Examples of the visual stimuli in each of the five levels of head orientation. b, Normalized fMRI signal, averaged across subjects, with separate bar graphs for each region of interest (top row, from left to right, areas AM, AL, ML, and PL; bottom row, from left to right, amygdala, area AF and area MF). The color of each bar reflects the condition (see a for legend). Blue asterisk indicates that, for all three subjects, there was a significant difference in the response to the zero orientation (0°) condition compared with the response in all other orientation conditions. Error bars reflect ± SEM. c, Examples of the visual stimuli in each of the five levels of facial expression. d, Normalized fMRI signal, averaged across subjects, with separate bar graphs for each region of interest (top row, from left to right, areas AM, AL, ML, and PL; bottom row, from left to right, amygdala, area AF, and area MF). The color of each bar reflects the condition (see c for legend). Red asterisk indicates that, for all three subjects, there was a significant difference in the response to the Ne condition compared with the response to all other expression conditions. Error bars reflect ± SEM.