All right, as a quick recap, erectile dysfunction is the inability to develop or maintain an erection and it could have psychological or organic causes.

好！简单总结下：勃起功能障碍是指无法勃起或维持勃起，可能由精神心理因素或器质性病因造成。

Often , it is true, this air of hardness is due not to psychological causes, but to the contemporary habit of over-painting.

实际上，这种冷漠的神态往往不是心理因素造成的，而是因为人们在现在时代养成了浓妆艳抹的习惯。

Though the psychological causes are still debated, there is a human tendency to over or under estimate the value of a reward based on its temporal proximity. This is often referred to as Temporal Discounting.

尽管拖延症的心理成因尚未形成定论，但是人类会倾向于根据时间距离的远近，夸大或低估某个回报的价值。这种现象通常被称为时间贴现。