Layers
The Layers tab in the Overlay Toolbox contains controls for display of data maps on surfaces or in volumes.

- By default, 3 layers are loaded into the Layers tab. The top layer of displayed data is listed as the first row, the second layer below that, etc., like a layer cake.

- Checkboxes under On at the left indicate whether the data listed for that layer is being displayed. When a top layer is unchecked, the layers underneath that layer are visible.

- Clicking the button opens the Overlay and Map Settings box that contains several tabs for setting display options for the different types of Layers data: Labels, Layer (volume layer settings), Metadata, Palette, Parcels, Trajectory.

- Clicking the button toggles on the colorbar for the displayed layer's palette. The values at the top of the colorbar change with each map to match the range of data displayed.

- Clicking the button shows options for moving, adding and removing layers relative to the layer in which this button was selected.

- Opacity sets the opacity of the layer. 1.0 is 100% opaque. If the opacity is set to a low value, layers under the selected layer will show through.

- The File pulldown sets the file to display on that layer. Only loaded files that can be displayed in the type of view set for the Active Tab will be options. Files can contain one or more brain Maps that may be selected by number or name in the pulldowns to the right.

- Yoke sets map yoking between layers to a map yoking group denoted by a Roman numeral. Navigation between maps of layers in the same map yoking group will be yoked (move together). If files with differing numbers of maps are set to the same map yoking group, a warning will appear before yoking is activated.