Why grief is so painful – and critical to the human race

Whether we’re dealing with the death of a loved one, the pain of heartbreak or the end of a career, loss can feel unbearable. But grief is a natural part of life with deep roots in our evolutionary history.

Grief begins in the brain, but it affects the whole body. The moment we learn of our loss, our brain triggers the fight-or-flight response. This heightened state puts extra stress on our organs and bodily functions, and we would usually experience it for a few minutes to 48 hours. But after bereavement, the effects of the fight-or-flight response can continue for months. Even years later, being reminded of our loss can retrigger the response.

Though we’ve been led to believe grief has a trajectory of five stages – denial, anger, bargaining, depression and acceptance – it’s really a non-linear process and its emotions can overlap, fade and reappear over time.

• Listen to the Instant Genius Podcast: The Neuroscience of Grief, with Mary-Frances O’Connor

Psychologists believe these feelings associated with loss evolved when we started to survive by way of collaboration and community.

In the beginning, we yearn for what we’ve lost, which would’ve encouraged us to look for missing members of our group. Later, we become more ruminating, as our brain turns toward protecting us and our group against future losses.

In becoming a social species, we started to form deep, emotional attachments. By their very nature, these relationships have to be meaningful – to forgo the pain of grief, we’d also have to give up our ability to love.

Read more:

• Why have we evolved emotional pain?
• How should you grieve?
• Why does sadness produce tears?
• The psychology of grief: Why losing a pet dog or cat is like losing a family member

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