Emotionally loaded visual stimuli have shown increased activation in visual and cortex limbic areas. However, differences in visual features of such images could confound these findings. In order to manipulate valence of stimuli while keeping visual features largely unchanged, we took advantage of an "expressional transfiguration" (ET) effect of faces. In addition, we used repetition effects, which enabled us to test more incisively the impact of the ET effect. Using the ET manipulation, we have shown that the activation in lateral occipital complex (LOC) was unaffected by valence attributes, but produced significant modulation of fMR adaptation. Contrary to LOC, amygdala activation was increased by ET manipulation unrelated to the adaptation. A correlation between amygdala and LOC adaptation points to a possible modulatory role of the amygdala upon visual cortex short-term plasticity.
Bibliographical noteFunding Information:
This study was funded by Adams Super Center for Brain Research, Tel Aviv University, and by Israel Science Foundation grants 8009, 38507 to R. Malach and T. Hendler, respectively. We thank our anonymous reviewers for their constructive remarks, U. Hasson for superb graphics ideas, I. Levy for the help with the retinotopic mapping, M. Harel for help with the brain flattening, P. Pianka for editing the last draft, D. Ben-Bashat for the physicist insights, G. Rotshtein and I. Kahn for the homemade software, D. Palti, M. Bleich, M. Ben Shachar, and Y. Yeshurun for the constructive discussions, and finally all the subjects who volunteered to participate in the various experiments.
ASJC Scopus subject areas
- Neuroscience (all)