New Books in Neuroscience · New Books Network

Judith Grisel, "Never Enough: The Neuroscience and Experience of Addiction" (Doubleday, 2019)

August 4, 2025·1 hr·5 clips
Emily Dufton opens the conversation as part of New Books in Drugs, Addiction, and Recovery on the New Books Network. Judith Grisel joins to talk about addiction through the brain's compensatory response to drugs. The basic idea is simple but unsettling: people often take a substance for one effect and, over time, get the opposite. Grisel walks through that pattern with concrete examples. A drug meant to help you relax can eventually make you tense, one taken for sleep can lead to insomnia, and one taken for energy can leave you tired. Caffeine is the clearest case because it blocks adenosine receptors, and repeated use can make those receptors increase. Melatonin is treated differently. Grisel says it does not affect the brain directly in the same way, so it does not trigger the same counter-response. Tryptophan gets the fuller over-the-counter explanation as an example that does show reduction over time. She describes it as the precursor to serotonin, which in turn is the precursor to melatonin. The discussion keeps coming back to the larger point that the brain pushes back against chemical change. Near the end, Grisel says she wants to learn more about addiction and recovery, and she points to sex differences as a neglected area that now looks more important. The interview also briefly turns to teenage brains, with a parent's hope that better research can help young people make their own decisions.

As heard by us

A careful conversation that turns addiction science into plain terms without flattening it.

The piece tracks a clear through-line: some drug effects can push the body toward the opposite of the relief people expect. It keeps the science legible by moving through caffeine, melatonin, and tryptophan instead of staying abstract, and the examples land because they stay…

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Want a clear guide to how drugs can push the brain toward the opposite effect?

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