Fixed case where there is no HRF data

    ml = plotprobe.dataTree.currElem.GetMeasList(iBlk);

    lst = find(ml.MeasList(:,4)==1);

    mlVis = ml.MeasListVis(lst);

    if ~isempty(plotprobe.handles.data{iBlk})

        if plotprobe.tMarkShow

            set(plotprobe.handles.data{iBlk}(logical(mlVis), 4:end), 'visible','on');

        else

            set(plotprobe.handles.data{iBlk}(:,4:end), 'visible', 'off');    

        end

    end

end