In The Art of Happiness, psychiatrist Howard C. Cutler interviewed His Holiness the Dalai Lama. The result of his study is a combination of traditional Tibetan Buddhist spiritual practice with Western therapeutic techniques and methods.
This whiteboard animation provides the TL;DR takeaway:
Mindfulness is the state of complete awareness, and it can be generated by meditation. Meditation is key because it helps us to control our attention – which is why we’re so aware of our bodies when doing yoga. Moreover, meditation actually increases gray matter in the brain regions that control attention.
So, how does mindfulness promote well-being?
It does this by stimulating the parasympathetic nervous system (PNS). We stimulate our PNS when we’re mindful. (Insert penis joke here.)
The PNS is related to the sympathetic nervous system (SNS) which activates what is often termed the fight or flight response. The PNS reduces the heart rate and makes us feel calm and restful. In this way, being mindful helps us to feel happy and more relaxed.
The second approach is to think about what the Dali Lama calls "wholesome intentions" which generate positive neurological effects in all regions of the brain. brain regions from the limbic system to the prefrontal cortex to release neurotransmitters that make you feel good.
When our intentions toward others are good, we find that any feelings of anxiety or insecurity we may have are greatly reduced. We experience liberation from our habitual preoccupation with self and paradoxically, this gives rise to strong feelings of confidence. - Dali Lama
Achieving success triggers brain chemistry to make us feel good for a while but an endless craving for it can cause us to feel dissatisfied, and even depressed. Composure enables us to recognize that we’ll be happier if we don’t long constantly for it. When our sense of self grows beyond our control it leads to suffering. When we identify with things, such as “This is my Tesla,” or “I am this belief system.”
Everything in the world ultimately comes to an end, our over-identification with things means that eventually, we experience loss and, subsequently, suffering.
In other words, by identifying with things we make their fate our own.
The practice of Zen isn’t geared toward reaching a result. This is hard for us to grasp. When we engage in an action, the goal is to achieve something else, like fame, recognition or money.
But for Zen, the intention is to do things without seeking any extra achievement. The activity in question can be absolutely anything, from cleaning to cooking, making art or meditating. As long as the aim is to get rid of everything that isn’t purely the action in which you are engaged.
That Dalai Lama teaches that if you have practiced meditation and feel proud of doing so, you should let go of this pride. Simultaneously, any disappointment should be set aside. Only the activity itself is of importance.
A disciplined mind leads to happiness, and an undisciplined mind leads to suffering. ― Dalai Lama XIV, The Art of Happiness