After a 3 s retention interval participants had to reproduce the sequence by clicking in the boxes in the correct order. At trial onset the fixation spot and placeholders were presented for 1000 ms. Memoranda were indicated by a 250 ms luminance change at a placeholder. There was a 250 ms delay between consecutive items in a sequence. After presentation of the final item, the placeholder array disappeared and participants maintained fixation for 4000 ms. The array then reappeared and participants were required to click the squares
in the order they find more flashed. Each placeholder measured 2.2° × 2.2° visual angle and the array of locations measured 7.2° visual angle in height and width. The center of the array was 4.4° from fixation. In the abducted condition, immediately after the offset MAPK inhibitor of the grid, and on hearing a beep, the experimenter rotated participants to the front. The grid was then represented and participants were required to click in the boxes in the order they flashed. Participants were presented with matrices in which half of the squares were white and the other half were black (Fig. 2B). Participants were required to reproduce the pattern in an empty grid. Patterns started with 8 squares (2 × 4 grid) in which 4 squares were black, and increased by two squares each time up to a maximum of 20 squares (10 black). Patterns were randomly generated
by E-prime. The grid could not be more than 3 squares wide. Each square measured 2.1° of visual angle, and the grid extended to a maximum width of 7.3° visual angle from fixation and a maximum height of 9.1° visual angle above and below the fixation spot. Participants completed three trials at each level and were required to get at least
two out of three trials correct in order to progress to the next level, where two additional squares were added to the matrix. Visual span was taken as the highest number of black squares that participants Pyruvate dehydrogenase lipoamide kinase isozyme 1 could correctly recall. At the start of each trial participants were presented with the fixation spot and the empty grid for 1000 ms. The matrix to-be-remembered was then presented for 1500 ms. At the offset of the pattern a beep sounded, instructing the experimenter to rotate the participants back to the front in the abducted conditions. The fixation spot remained present for 4000 ms before an empty grid was presented. Participants were required to click the squares that were previously shaded. Once clicked, the square went black. Electro-oculographic eye movement data were recorded throughout the trials using an MP35 acquisition unit and BSL Pro 3.7 software (Biopac Systems Inc., CA, USA). Three shielded 4 mm AgCl electrodes were attached to the participants’ skin using adhesive disks, and electrode gel was used to improve recording conductance.