Preliminary report on the association between pulvinar volume and the ability to detect backward-masked facial features

Description: Abstract: Although backward masking is a powerful experimental tool in mitigating visual awareness of facial expressions of emotion, ~20% of participants consistently report being resistant to its effects. In our previous studies, we excluded these participants from analysis as we focused on neural data in individuals who were subjectively unaware of backward-masked facial features that were presented for a brief period of time (e.g., 17 ms). Here, we shifted our focus to potential structural brain difference between aware and unaware participants. To achieve this, structural magnetic resonance imaging (MRI) data were pooled from two recent backward masking studies of emotional faces or eye whites. Out of a total of 64 participants, 12 reported being subjectively aware of the masked faces or their facial features. Whole-brain, voxel-based morphometric (VBM) analysis of structural MRI data yielded significantly greater volume of the posterior thalamus, including the bilateral pulvinar, for the subjectively aware versus unaware individuals. The present findings offer a neuroanatomical basis for visual awareness of emotional content in the form of backward-masked facial features, which complements the known functional role of the pulvinar in such neurobehavioral processes. Notes: VBM analyses were performed using the VBM8 toolbox for SPM8. Default parameters were used for preprocessing (please refer to the VBM8 online manual: http://dbm.neuro.uni-jena.de/vbm8/vbm8-manual.pdf). For group level analysis, a voxelwise two-sample t-test was used to compare the aware versus unaware groups while controlling for intracranial volume (ICV), study (2010 or 2016), age, and sex. Group level t-map is stored as spmT_0001.nii (ID 55030). Please refer to the images meta data for the experimental variables and covariates. Please use the following link to access the published article associated with this dataset (http://www.sciencedirect.com/science/article/pii/S0028393217304104). For detailed data processing steps, please refer to this article. Kim MJ, Mattek AM, Burr D & Whalen PJ (in press). Preliminary report on the association between pulvinar volume and the ability to detect backward-masked facial features. Neuropsychologia. doi:10.1016/j.neuropsychologia.2017.10.034

Related article: http://doi.org/10.1016/j.neuropsychologia.2017.10.034