The phase encoding design was similar to procedures widely used for retinotopic mapping (Bandettini et al., 1993 and Schneider

et al., 2004). A transparent wedge within a dark foreground rotated around a central fixation point. The underlying checkerboard was only visible through the transparent wedge, giving the appearance of a rotating checkerboard wedge (Swisher Cabozantinib in vitro et al., 2007). The wedge rotated either clockwise or counterclockwise and spanned 1°–15° in eccentricity with an arc length of 75°. The chromaticity and luminance of each check of the colored checkerboard alternated at a flicker frequency of 4 Hz. To ensure proper fixation, subjects performed a luminance detection task on the fixation point. Luminance changes of the fixation point

occurred every 2 to 5 s for the duration of 0.09 s. SM and control subjects performed with an accuracy of 93% and 91% ± 7%, respectively. Each run was composed of eight 40 s cycles of the rotating wedge. Runs alternated between clockwise and counterclockwise wedge rotation, with a total of 12 runs per scanning session. Using fMR-A paradigms, High Content Screening we investigated neural representations of different types of objects including 2D objects, 3D objects, and line drawings of objects as well as size and viewpoint invariance (Figure 2). For each fMR-A study, 51 gray-scale images of 2D objects, 3D objects, or line drawings were used. The objects were subdivided into a matrix of equally sized rectangulars (25 along the horizontal dimension and 25 along the vertical dimension). Subsequently, the rectangulars were randomly re-arranged resulting in 51 scrambled images per study. The stimuli subtended approximately 18° × 18° of visual angle centered over a fixation point on a gray background. 2D and 3D objects were generated

with MATLAB software (The MathWorks; Natick, MA); line drawings were chosen from the ClipArt Gallery (http://office.microsoft.com/). For the size-invariance study, the 2D objects were changed in size, resulting in 16 different sizes of each object over a range of 6.75° × 6.75° to 18° × 18°. For the viewpoint-invariance study, the 3D objects were rotated around the y axis, resulting in 16 different viewpoints Rolziracetam of each object covering a range of ±75°. In the adapted condition, the same object was presented 16 times. In the non-adapted condition, 16 different objects were presented once. Similar stimulus sets and fMR-A paradigms have been successfully used in our previous study ( Konen and Kastner, 2008). Each fMR-A study consisted of three scans, each of which contained epochs of intact and scrambled object presentations. Each epoch lasted for 16 s and was alternated with equally long blank periods. In each epoch, 16 intact or scrambled objects were presented for 750 ms each interposed with 250 ms blank periods. Each scan started and ended with a blank period of 16 s.