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Responses were made using MR compatible fiber-optic button boxes. Imaging data were collected at the Wellcome Trust Centre for Neuroimaging using a 3-T Siemens Allegra Scanner with an 8-channel head coil. Anatomical images were acquired using a 3D MDEFT sequence (Deichmann et al., 2004) with a sagittal partition direction yielding images with 1-mm isovoxel resolution (time repetition (TR)?=?7.92?ms, time echo (TE)?=?7.92?ms, flip angle?=?15��). Whole-brain echoplanar functional images were acquired in 38 transverse slices (TR?=?2280?ms, TE?=?30?ms, matrix?=?64?��?72, field of view?=?216?mm, slice thickness?=?2mm, 1?mm gap, descending slice acquisition order). Additionally, a double-echo FLASH field mapping sequence was collected to measure GSK3B the distribution of field inhomogeneities (TE1?=?10?ms, TE2?=?12.46?ms, 3?��?3?��?2?mm resolution with 1?mm gap). Data were processed using SPM8 (http://www.fil.ion.ucl.ac.uk/spm). Functional images collected from the scanner were slice-time corrected, aligned with a representative functional volume and motion corrected using an unwarping procedure that employed field inhomogeneity information from the field mapping scans, and spatially smoothed using a 4-mm full-width at half maximum Gaussian kernel. Structural images were also aligned with the representative functional volume. For the main experiment, separate events representing target position, distractor position and distractor congruency were modeled using a general linear model (GLM). These events were modeled as impulses of activity at the onset of the stimuli and SAHA HDAC datasheet were convolved with the canonical hemodynamic response function (HRF) included with SPM8. For the retinotopic and localizer scans, boxcars representing the duration of each block were convolved with the HRF and similarly modeled using a GLM. Results of the analyses, in the form of statistical maps, were overlaid on the structural images collected for each subject. For group-level analyses, these statistical maps were spatially normalized to the standard Montreal Neurological Institute space and entered into a one-way t-test to produce group average statistical maps, which were then overlaid onto an average structural image. To examine which regions of the http://www.selleckchem.com/products/tariquidar.html cortex showed greater blood oxygen-level dependent (BOLD) responses to the various trial types, the group-level maps were generated using an uncorrected voxel-level threshold of p?
