6
" Whatever the evolutionary precursors of drug use are, a permanently “drug-free” human culture has yet to be discovered. Like music, language, art, and tool use, the pursuit of altered states of consciousness is a human universal. With access to few alternatives, Siberian shamans imbibe reindeer and human urine to maximize the psychedelic yield of Amanita muscaria mushrooms (the metabolite that is excreted may be stronger than the substance initially ingested); on nearly the opposite side of the world, New Zealanders party with untested “research chemicals” synthesized by Chinese chemists. Drug use spans time and culture. It is a rare human who has never taken a drug to alter her mood; statistically, it is non-users who are abnormal. Indeed, today, around two thirds of Americans over 12 have had at least one drink in the last year, and 1 in 5 are current smokers. (In the 1940s and ’50s, a whopping 67% of men smoked.) Among people ages 21 to 25, 60% have taken an illegal drug at least once—overwhelmingly marijuana—and 20% have taken one in the past month. Moreover, around half of us could suffer from physical withdrawal symptoms if denied our daily coffee. While Americans are relatively prodigious drug users—topping the charts in the use of many substances—we are far from alone in our psychoactive predilections. "
― Maia Szalavitz , Unbroken Brain: A Revolutionary New Way of Understanding Addiction
8
" In addiction, this means that because being addicted escalates wanting more than liking, the drug experience gets deeply carved into your memory. Anything you can associate with achieving a drug high, you will. As a result, when you try to quit, everything from a spoon (you could use it to prepare drugs) to a street (this is where the dealer lives!) to stress (when I feel like this, I need drugs) can come to drive craving. Desire fuels learning, whether it is normal learning or the pathological “overlearning” that occurs in addiction. You learn what interests you with ease because desire motivates. In contrast, it’s far more difficult to learn something you don’t want to understand or care to comprehend. Berridge and Robinson’s research also helps resolve another paradox: If dopamine signifies pleasure, then the brain should become less and less responsive to it as tolerance to a drug develops. But while tolerance clearly does occur, the opposite result is also seen in the brain. As I took cocaine, paranoia began to set in at lower and lower doses—not higher ones. The summer of 1988, it also took increasingly less drug to achieve the state of heart-pounding anxiety and mortal dread that I experienced so frequently. Neuroscientist Marc Lewis described his experience of this effect in his addiction memoir this way: “I kept pumping [cocaine] into my vein, this non-sterile solution, until my reeling consciousness, nausea, racing heart, and bloated capillaries told me that death was near. Later that night, I begged myself to stop.… But the urge would not relent. "
― Maia Szalavitz , Unbroken Brain: A Revolutionary New Way of Understanding Addiction
10
" However, repeating the experiments and expanding on them led the researchers to a different conclusion. While dopamine is involved in motivation or the pleasures of the hunt, that’s not the only way we can feel good. Dopamine is not necessary, it seems, for enjoying sweetness, comfort, satiation, and calmness—research suggests that these pleasures are more strongly linked to the brain’s natural opioids, or heroin-like chemicals, instead of to dopamine. And this has implications for the broader understanding of addiction. "
― Maia Szalavitz , Unbroken Brain: A Revolutionary New Way of Understanding Addiction
17
" In Berridge and Robinson’s view, pleasure is divided into “wanting” (hunt) and “liking” (feast). As we’ll see, the distinction is especially important in addiction because each type has a different influence on learning. Like many discoveries in science, this one was made when the researchers were trying to understand why an experiment didn’t work out as they’d predicted. They’d used a chemical that selectively destroys dopamine cells in the nucleus accumbens of rats to eliminate their “pleasure centers.” Not surprisingly, after these key dopamine cells were eliminated, the rodents became so amotivated that if the researchers hadn’t manually fed them, they would have starved to death. “They wouldn’t want to eat. They wouldn’t want to drink,” Berridge says. “We’d have to artificially nurse them and artificially feed them, the way you would in a hospital intensive care ward.” The rats behaved as though they had extremely severe Parkinson’s, which they essentially did. Destroying their dopamine cells had taken away their motivation, leaving them with no desire or will to do anything at all, even what was necessary for survival. "
― Maia Szalavitz , Unbroken Brain: A Revolutionary New Way of Understanding Addiction
