There can be both an indirect and direct way to achieve this. The reflex erection is the direct way, achieved by touching your penis to trigger the nerves in the lower part of your spinal cord and your peripheral nervous system. The psychogenic erection is the indirect way, via non-mechanical sexual stimulation (visual, for example) and sexual arousal. This activates the limbic system in your brain, sending electrical signals down to your erectile nerve centres via the lower regions of your spinal cord. The latter is why you can get both nocturnal or "morning glory" erections, rather non-erotically referred to as nocturnal penile tumescence. How romantic.
"If any of these physiological factors don't work properly, a man can experience weak erections," says Axe. "Problems maintaining an erection can be due to a number of issues, from hormone imbalances, to neurological issues, cardiovascular conditions, stress and issues with your mental health. There is not one clear way to explain erectile dysfunction — it depends on the man and his specific health condition."
Does drinking water help with Ed?
"Stress and anxiety can adversely affect sexual performance and are common causes of erectile dysfunction,” warns Feloney. “Feelings of stress and anxiety can also lead to depression and a loss of interest in sex." It's important to get these feelings out in the open where you can deal with them. Issues that can lead to erectile dysfunction include fear from previous bad experiences with sex, family or work related stress, poor communication with your partner, and unrealistic goals and expectations.