t = 0:0.001:10;
x = randn(size(t));
selection = x(t > 5 & t < 6);

figure()
hold on
plot(t, x, 'displayname', 'measurements')
plot(t(t > 5 & t < 6), selection, 'displayname', 'selection')
xlabel('Time [s]')
ylabel('Intensity')
legend 'show'
box 'off'