According to the screenshot provided (thanks for those) it is legend items that are selected in the layout view and not map layers. Though these are similar, they are not the same. Toggling the visibility of layers (within a map) should be the same whether you are in Map View or in Layout View. In the layout view you find the layer underneath the map frame node.
Toggling the visibility of selected legenditems can be done by selecting the items and while pressing the ctrl key clicking the visibility box of one of the selected legend items. This can also be achieved by pressing the space bar after selecting the items.