The United States is awash in debt. Median household debt has risen to more than $100,000 from less than $60,000 in 1990, even as median incomes have increased only slightly. Much of the debt is held by workers who are building up loans on credit cards, or obtaining dubious mortgages in a bid to secure some fraction of the lifestyle of an upper class that keeps getting richer. This increase in debt has occurred as the gap between the rich and the poor has continued to widen and the visibility of coveted luxury goods on television and the Internet has continued to grow.

Some laud the democratization of credit, seeing its availability to wider swaths of the American population as broadening opportunity; some criticize it as the ruthless seduction by financial institutions of working people who will one day face bankruptcy because they will be unable to pay credit card bills and mortgages.

But this is much clear: the spread of debt is one of the most significant social phenomena in the United States today, allowing the less affluent to spend more than they have. As long as interest rates do not rise steeply, this will continue to happen.

   Children who experience social anxiety—feeling discomfort or distress in social situations—or who are socially incompetent are particularly at risk for developing dependence on electronic media. This is true whether the preferred agent be the Internet, video games, or a smartphone. The more a child hides behind a screen, the more socially awkward he or she becomes, creating a self-perpetuating cycle. In contrast, a shy child who continually works at overcoming social anxiety is likely to overcome it. In the past, the strong desire to belong to a social group during adolescence helped override resistance to social interaction, which would lessen over time simply due to practice. Nowadays, socially anxious or awkward children and teens aren’t forced to practice face-to-face and eye-to-eye interaction because some of their social needs are met online. Thus, in socially anxious children, the ability to tolerate the physical presence of others never builds, and “walls”are erected instead to keep the child feeling safe. An adolescent with somewhat poor social skills in high school can easily become reclusive as a young adult, spending more and more hours online and less and less time interacting in real life. This pattern makes it increasingly harder to make and keep friends. Relationship problems show up at home, too; research indicates that the more time a child spends using the Internet, the less healthy the parent-child relationship becomes. Thus, social incompetence and screen-time represent another bidirectional relationship.

　　Post-traumatic stress disorder is a malady of memory. Sufferers are often haunted by recurrent nightmares, distressing thoughts and flashbacks so intense in color, smell and sound that they feel as if they are reliving the trauma. But what if these unbearable memories could be selectively erased? Sheena Josselyn, a professor of physiology and psychology, who studies how the brain encodes, stores and uses information, is intrigued by the idea and has been investigating how to “silence” memories --make them temporarily inaccessible-- in mice. She thinks it’s possible that a variation of this technique could one day help treat post-traumatic stress disorder in humans. 

　　Studies with mice have found that although their brains contain billions of neurons, only a few are necessary to form a fearful memory. Researchers working with mice began by teaching them to fear a tone: when it sounds, they feel a mild shock to their feet (not to hurt them, just to scare them). The next time the mice hear the tone, they crouch and freeze, signaling fear. The researchers discovered that they could trigger the memory of that fear even without presenting the tone. They did this by stimulating the small group of nerve cells holding that memory through a technology called optogenetics. Using the same technology, they found they could also suppress the fearful memory. With optogenetics, scientists insert proteins into neurons to make them sensitive to light. Depending on the type of protein and color of light used, these cells can then be activated or deactivated by shining pulses of the light directly into the brain. If the light activates the cells, the mice freeze as if they’ve just heard the tone. If the light deactivates the cells, the memory is suppressed. While optogenetics is an invasive procedure and technologically not feasible with humans, Josselyn hopes that the general principles learned from these studies could eventually help scientists create new drugs for treating memory disorders such as post-traumatic stress disorder and Alzheimer’s. 

　　But should you erase a bad memory? Absolutely not, says Josselyn. She emphasizes that this future technology should not be applied to everyday bad things, and that these discoveries need to go hand in hand with a real thinking about the ethics involved in potentially manipulating memories in people. Their use would only be considered in extreme cases after all other treatment options have been explored. The goal is not to sanitize life or make people super happy, but rather to make everyone a functional person, capable of moments of joy.