Abstract
The visual system processes social stimuli such as faces and bodies, differently than other objects (Maurer, Le Grand, & Mondloch, 2002; Peelen & Downing, 2007). While processing of faces (Yin, 1969) and bodies (Reed et al., 2003) is disrupted by inversion, object processing is less disrupted (Stein, Sterzer & Peelen, 2012). Bernard et al.’s Sexualized Body Inversion Hypothesis (SBIH) suggests that female bodies are objectified are therefore processed by the visual system as objects (2012). This hypothesis is supported by evidence of a greater inversion effect for male than female body images in a discrimination task. However, physical differences between the two image sets (male, female) may account for these differences. Using an ideal observer analysis, we quantified discriminability of the male and female images in this set. We then tested whether, after accounting for discriminability, there still was a residual effect supporting the SBIH. Although the discriminability of images predicted participants’ performance (F(1,43) = −2.82, p < .001), there was still a reliable residual difference in the inversion effects across the stimulus sets, supporting the SBIH (F(1,43) = 4.99, p = .03). In a second experiment, we tested how varying degrees of sexualization affect objectification of bodies. To manipulate sexualization, each target image was paired with an audio file containing information rated as high or low in sexuality. Audio files were independently rated. Participants’ performance was impacted by the model’s level of sexuality. Across target sex, less sexualized targets were perceptually processed like social stimuli, while highly sexualized targets were processed as objects, evidenced by the size of the inversion effect (F(1,37) = 3.21, p = .066). Overall, we did find support for the SBIH, and our results suggest that male and female bodies can be perceptually objectified depending on degree of sexualization.
Acknowledgement: National Science and Engineering Research Council (Canada)