Comparing electrodes having retinotopic labels, using Common Average Reference (CAR), Current Source Density (CSD) or broadband gamma power (Gamma). To the left of each row, the number and retinotopic label of each electrode is specified. For each method, the scale is specified in the first row. Insets for broadband gamma power signals, electrodes 34 and 67, show a magnified y-scale in order to better view the responses. Missing electrodes in CSD were excluded from the analysis because they reside on the edge of the occipital strip and therefore are not appropriate for CSD estimation. Missing electrodes in the broadband gamma power case did not show a significant OLE (see Table 1)