In the early 2010s, rates of anxiety, depression, self-harm and suicide began rising sharply among adolescents, especially girls, across the U.S., UK, Canada and other Western nations. Key trends:

• Depression rates roughly tripled among teen girls and doubled among teen boys in the U.S. between 2010-2020
• Rates of self-harm nearly tripled for younger adolescent girls
• Suicide rates rose dramatically, especially for younger teen girls
• Similar patterns emerged in the UK, Canada, Australia, and across Western Europe at the same time No other theory, such as the 2008 financial crisis or concerns about school shootings and climate change, can explain this sudden, synchronized international increase in teen mental illness. The main factor that changed in the early 2010s was adolescents rapidly transitioning from basic cell phones to smartphones with social media.

Section: 1, Chapter: 1

Author: Jonathan Haidt

The rising generation, despite receiving unprecedented mental health accommodations and resources, has become the loneliest, most anxious, depressed, pessimistic, and helpless cohort on record. 42% have a diagnosed mental illness. Therapists insist this is because young people face more stressors than ever, like smartphones, the pandemic, and climate change. But the author argues youth mental health has been declining for decades before these factors. She believes the real problem may be the mental health system itself - convincing kids they are disordered, inculcating feelings of helplessness, and inhibiting normal development.

Section: 1, Chapter: 0

Author: Abigail Shrier

Many Vietnam war veterans continued to be haunted by their traumatic combat experiences years or decades later, unable to move on with their lives. Their trauma infiltrated every aspect of their lives, making it difficult to maintain relationships, find satisfaction in work, and control intense emotions like rage. Trauma leaves an imprint on mind, brain, and body that persists long after the original event. Healing requires finding ways to come fully alive in the present rather than remaining stuck in the past.

Section: 1, Chapter: 1

Author: Bessel van der Kolk

One key function of REM sleep and dreaming is to help process difficult emotional experiences from waking life. REM sleep:

• Reduces the emotional charge of "painful, even traumatic" experiences
• Disentangles the emotion from the factual details of the memory
• Allows the emotional memory to be stored without the same degree of emotional distress

The mechanism works by:

• Reactivating emotional memory circuits during REM sleep when stress neurochemicals like noradrenaline are suppressed
• Allowing the brain to re-process the experience in this neutral, "safe" environment
• Stripping the memory of its emotional charge so it can be filed away with less distress

Evidence shows people who are able to achieve REM sleep and dream about emotional experiences after a trauma have better long-term mental health outcomes. They are less likely to develop PTSD, depression and anxiety.

Section: 3, Chapter: 10

Author: Matthew Walker

Chapter 15 details the complex effects of stress on memory formation and retrieval.

• Acute stress causes release of hormones epinephrine and cortisol, which signal the amygdala to activate the hippocampus to consolidate the stressful event as a memory. This prioritizes storage of important, survival-relevant information.
• An optimal amount of acute stress improves attention and memory formation. Too little stress and consolidation isn't boosted.
• Chronic stress leads to prolonged cortisol release, impairing the hippocampus and its ability to form new memories. It can even cause hippocampal neurons to wither and die.
• Techniques like meditation, exercise, yoga and reframing negative thoughts can reduce perceived stress and protect the brain from its memory-harming effects.

Section: 3, Chapter: 15

Author: Lisa Genova

Studies by Dr. Jim Coan and colleagues demonstrate the powerful impact of close relationships on regulating emotions and stress responses:

• Happily married women showed less stress response in their brain when holding their husband's hand during a mildly painful experience
• Unhappily married individuals showed higher blood pressure in their spouse's presence compared to being alone

When our innate attachment needs are not met, both our emotional and physical health are compromised. The lesson is to choose a partner carefully as they will literally shape our mind and body.

Section: 0, Chapter: 2

Author: Amir Levine, Rachel Heller