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. 
      - 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. 
      - 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. 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. 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. 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.
      
      - 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.  
 
    