کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
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6264924 | 1614058 | 2011 | 8 صفحه PDF | دانلود رایگان |
![عکس صفحه اول مقاله: Research ReportRecognising upright and inverted faces: MEG source localisation Research ReportRecognising upright and inverted faces: MEG source localisation](/preview/png/6264924.png)
Face recognition is a complex cognitive task that involves a distributed network of neural sources. While some components of this network have been identified, the temporal sequence of these components is not well understood. Magnetoencephalography (MEG), analyzed with a spatial filtering source localisation algorithm, was used to determine frontal contributions to face recognition. We tested 22 adults (mean age 26.3Â years; 10 females). Upright and inverted faces were presented in counter-balanced blocks and subjects identified repetitions in a 1-back protocol. MEG data were recorded continuously from a 151 channel CTF machine and source localised to each participant's MRI. The classic face components, M100 and M170, were seen for upright and inverted faces with M100 localizing to bilateral occipital areas and M170 to bilateral fusiform areas. A third component, M240, showed high global field power to correctly recognised repeated faces and localised to right middle frontal and insula sources at 240Â ms for upright faces and bilateral mid-frontal sources for inverted faces. The effect of repetition was examined and a source identified at 250Â ms in the cingulate, for inverted faces. These results provide timing information on frontal lobe activation, seen reliably in fMRI memory studies; the immediate recognition of repeated faces activates the right frontal sources at 240-250Â ms, with bilateral activation to repeated inverted faces, perhaps due to increased task difficulty.
Research HighlightsâºMEG was analyzed to determine frontal sources for face recognition. âºM240 sources to recognised upright faces were seen in right mid-frontal and insula. âºBilateral M240 mid-frontal sources were seen for recognised inverted faces. âºA repetition effect showed a source at 250 ms in the cingulate for inverted faces.
Journal: Brain Research - Volume 1381, 24 March 2011, Pages 167-174