Inter-Subject Synchronization of Prefrontal Cortex Hemodynamic Activity During Natural Viewing
Iiro P Jääskeläinen*, 1, 2, Katri Koskentalo1, 2, Marja H Balk1, 2, 3, Taina Autti3, Jaakko Kauramäki1, 2, Cajus Pomren1, 2, Mikko Sams1, 2
1 Department of Biomedical Engineering and Computational Science, Helsinki University of Technology, FIN-02015 TKK, Espoo, Finland
2 Advanced Magnetic Imaging Center, Helsinki University of Technology, FIN-02015 TKK, Espoo, Finland
3 Helsinki Medical Imaging Center, Helsinki University Central Hospital, Helsinki, Finland
Hemodynamic activity in occipital, temporal, and parietal cortical areas were recently shown to correlate across subjects during viewing of a 30-minute movie clip. However, most of the frontal cortex lacked between-subject correlations. Here we presented 12 healthy naïve volunteers with the first 72 minutes of a movie (“Crash”, 2005, Lions Gate Films) outside of the fMRI scanner to involve the subjects in the plot of the movie, followed by presentation of the last 36 minutes during fMRI scanning. We observed significant between-subjects correlation of fMRI activity in especially right hemisphere frontal cortical areas, in addition to the correlation of activity in temporal, occipital, and parietal areas. It is possible that this resulted from the subjects following the plot of the movie and being emotionally engaged in the movie during fMRI scanning. We further show that probabilistic independent component analysis (ICA) reveals meaningful activations in individual subjects during natural viewing.
Received Date: 25/2/2008 Revision Received Date: 8/3/2008 Acceptance Date: 12/3/2008 Electronic publication date: 1/4/2008 Collection year: 2008
2008 Bentham Science Publishers Ltd.
open-access license: This is an open access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.5/), which permits unrestrictive use, distribution, and reproduction in any medium, provided the original work is properly cited.
* Address correspondence to this author at the Department of Biomedical Engineering and Computational Science, Helsinki University of Technology, FIN-02015 TKK, Espoo, Finland; E-mail: firstname.lastname@example.org