The appropriate treatment for impotence depends upon whether the cause is physical or psychological.A man whose impotence is psychologically based generally still has erections during sleep whereas an individual whose impotence is physical in origin does not.One easy inexpensive way to test for noturnal erections is with postage stamps.Give a strip of stamps around the shaft of the penis before going to bed.If the ring of stamps is broken in the morning,the cause is likely psychological.if the strip is unbroken,the impotence is likely physiological.