asleyetracking com) sampling at 50 Hz MRI data were acquired on

asleyetracking.com) sampling at 50 Hz. MRI data were acquired on a 3T Magnetom selleck products Allegra head-only MRI scanner (Siemens Healthcare, Erlangen, Germany) operated with the standard transmit-receive head coil. Functional MRI data were acquired in three sessions with a blood oxygenation level-dependent (BOLD) sensitive T2*-weighted single-shot echo-planar imaging sequence which was optimized to minimize signal dropout in the medial temporal lobe (Weiskopf, Hutton, Josephs,

& Deichmann, 2006). The sequence used a descending slice acquisition order with a slice thickness of 2 mm, an interslice gap of 1 mm, and an in-plane resolution of 3 × 3 mm. Forty eight slices were

HSP inhibitor clinical trial collected covering the entire brain, resulting in a repetition time of 2.88 sec. The echo time was 30 msec and the flip angle 90°. All data were acquired at a −45° angle to the anterior–posterior axis. In addition, field maps were collected for subsequent distortion correction (Weiskopf et al., 2006). These were acquired with a double-echo gradient echo field map sequence (TE = 10 and 12.46 msec, TR = 1020 msec, matrix size 64 × 64, with 64 slices, voxel size = 3 mm3) covering the whole head. After these functional scans, a 3D MDEFT T1-weighted structural scan was acquired for each participant with 1 mm isotropic resolution (Deichmann, Schwarzbauer, & Turner, 2004). FMRI data were pre-processed using SPM8 (www.fil.ion.ucl.ac.uk/spm). The first 6 ‘dummy’ volumes from each of the three sessions were discarded to allow for T1 equilibration

effects. Images were realigned and unwarped (using the field maps) and normalised to a standard EPI template in MNI space with a resampled voxel size of 3 × 3 × 3 mm. Functional data were left unsmoothed for the decoding analyses to facilitate the detection of information present across patterns of voxels. Each trial was modelled as a separate regressor for the 6sec stimulus duration and convolved with the canonical haemodynamic response function. Catch trials were combined into a single regressor and, along with participant-specific movement regressors, were included as covariates of no interest. Participant-specific parameter estimates pertaining ADP ribosylation factor to each regressor (betas) were calculated for each voxel. Motivated by the findings of Auger et al. (2012), our main region of interest (ROI) was the RSC. In this previous study of item features, we found that the parahippocampal cortex (PHC) responded to permanence as well as to a range of other features (Auger et al., 2012). Interestingly, however, and unlike RSC, the PHC was not sensitive to differences between good and poor navigators. We therefore included PHC as a second ROI in our analysis. As in Auger et al.

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