Radiolab – "9-Volt Nirvana" (June 26, 2014)

Overview

This Radiolab episode, hosted by Jad Abumrad, Robert Krulwich, and Soren Wheeler, investigates transcranial direct current stimulation (tDCS)—a method of using mild electrical currents to the brain purportedly to accelerate learning, enhance performance, and even induce a "flow state." The story is framed by science journalist Sally Ady's firsthand experience as both a subject and investigator. The show probes the science, the military applications, the burgeoning DIY community, lingering uncertainties, and the strange allure of brain-zapping technology.

Key Discussion Points & Insights

1. Introduction to tDCS and Sally Ady’s Assignment

• Sally Ady, a London-based editor for New Scientist, recounts how her curiosity was piqued at DARPA Tech, a conference of defense researchers.
• She encountered a program claiming to speed up learning by applying electrical current to the brain.
  • “She was telling me about her program, which was that they had figured out how to apply sort of electrical current to the brain in order to accelerate the learning process. And I was like, no.” (Sally Ady, 02:34)
• This led Sally to join a sniper training simulation in Carlsbad, California, where tDCS was being tested.

2. The Sniper Simulation: Sally’s Experiment with tDCS

• The training mimics real-life situations (virtual enemies, situational pressure).
• Sally performs poorly under pressure, feeling overwhelmed, jetlagged, and anxious.
  • “And then from all over the place, dozens of people in suicide bomb vests start running at you... I can't make the decisions fast enough.” (Sally Ady, 04:42)
• Neuroscientist Mike Weisend, who leads the tDCS experiments, introduces the device: basic electrodes, a battery, and a simple circuit.
  • “So this is a big red toolbox that we got literally from Sears.” (Mike Wisen, 05:56)
• Sally receives stimulation (one electrode on her right temple, one on her left arm). She describes the sensation as metallic, “like I had licked the inside of an aluminum can.” (Sally Ady, 06:28)
• With tDCS on, Sally’s experience of time and task changes dramatically.
  • “She’s like, no, no, no, that was 20 minutes. Like, no, that’s not true... the clocks have all shifted by 20 minutes, and I swear to God, it was three minutes.” (Sally Ady, 07:07)
• Her performance switches from failing (3/20 hits) to perfect (20/20), and Sally feels “in the zone,” or in a state of flow.

3. How Does tDCS Work? (08:03–11:13)

• Mike Weisend explains the theory: early in learning, the brain tries several neural patterns; tDCS helps the “right” circuit fire and stick.
  • “We can double the rate of learning.” (Mike Wisen, 08:34)
  • “This is not a scalpel. This is a sledgehammer.” (Mike Wisen, 10:15)
• The tool is not precise—stimulating millions of neurons at once. But, by targeting specific brain regions (e.g., right side for spatial tasks, left for language), performance in targeted domains can improve.

4. Live Studio Test: Can Jad Be “Juiced Up”? (11:13–14:47)

• Mike brings his tDCS kit to the studio. Jad volunteers for a test.
• Before the current, Jad struggles to see hidden images in stereograms (3D pictures).
• With tDCS applied (“feels like a bunch of mosquitoes are biting me in my temple”), Jad experiences a sudden improvement:
  • “They’re coming out really fast... This is awesome. Coiled snake.” (Jad Abumrad, 14:15)
  • “I was like—you couldn't give them to me fast enough... Maybe that’s a flow state like you were describing.” (Jad Abumrad, 14:23)
• Jad and the hosts note uncertainties: placebo effect, adrenaline, and the need for controlled studies.

5. The Scientific View: Promise, Caveats, Dangers (15:09–16:56)

• Soren contacts Peter Reiner, neuroscientist at the University of British Columbia, for a reality check.
• Reiner notes genuine interest in the research, says tDCS "appears to be relatively effective," but cautions:
  • “Pretty much all of the studies that have been done to date are relatively small.” (Peter Reiner, 15:42)
• Most studies involve only 20–50 people; positive effects are promising, but not conclusive.

6. The DIY tDCS Movement—and Risks (16:28–18:45)

• YouTube is flooded with DIY instructions for making and using tDCS devices ("for around $20").
  • “Since I don’t have any solder with me... YouTube just seems to be filled with people who are trying to hotwire their own brain.” (Soren Wheeler, 16:49–16:56)
• Some users claim cognitive boosts; others report side effects—burns, temporary blindness, mood swings.
  • “After about five minutes, I felt really, like really angry and depressed...” (DIY user, 18:17)

7. The Brain as an Ecosystem: Ethical & Safety Concerns (18:45–19:41)

• Reiner warns this technology is hard to regulate, as device placement changes effects.
  • “Every part affects every other part in some way.” (Peter Reiner, 19:03)
  • tDCS’s impact can propagate throughout the nervous system, not just local brain regions.
  • The “zero sum theory”: enhancing one brain area may dampen another.

8. Aftereffects and Psychological Impact (19:41–22:03)

• Sally describes a surprising after-effect: post-experiment, she felt calm, anxiety-free, and unusually focused for “a couple of days.”
  • “The little angry gnomes in my head... they were just completely turned off, I think, for a couple of days.” (Sally Ady, 21:25)
  • “It was like somebody had wiped a really steamy window, and I was just able to look at the world for what it was.” (Sally Ady, 21:56)

9. Deeper Questions: Flow, Creativity, and the Nature of Control (22:03–24:33)

• The hosts consider whether shutting out one’s own self-doubts and anxieties is part of what makes for optimal performance.
• They debate the effect of being able to “order up” flow states or creativity on-demand.
  • Soren: “That’s a world that’s empty of true gratitude.” (24:25)

10. The Allure and the Risk of “Brain Juicing” (24:33–25:14)

• Sally admits she craved another session, likening the experience to a drug.
  • “It felt like a drug with no side effect. I mean, I don't know if I'm gonna get addicted to electricity. Seems unlikely...” (Sally Ady, 24:33)

Notable Quotes & Memorable Moments

• On the sensation of tDCS:
  • “It wasn’t so much that I suddenly tasted metal in my mouth. It tasted like I had licked the inside of an aluminum can.” (Sally Ady, 06:28)
• On performance improvement:
  • “When Sally did it with brain stimulation, she performed at 100% accuracy.” (Mike Wisen, 07:44)
  • “She went from being, like, totally inept to, like, a trained killer?” (Jad Abumrad, 08:03)
• On the risk of DIY:
  • “There's some people that report loss of consciousness after using it. There are some people that are reporting feeling burns. There's actually one report of somebody going temporarily blind.” (Nick Fitz quoting, 17:44–18:08)
• On anxiety relief:
  • “They were just completely turned off, I think, for a couple of days... It was like somebody had wiped a really steamy window, and I was just able to look at the world for what it was.” (Sally Ady, 21:25–21:56)
• On craving the experience:
  • “One of the really worrying things to me was afterward how much I craved doing it again.” (Sally Ady, 24:33)

Important Timestamps

| Timestamp | Segment Description | |------------|-----------------------------------------------------------------------| | 02:34 | Sally encounters tDCS at DARPA Tech | | 03:54 | Sally describes intense sniper simulation | | 05:54 | Introduction of neuroscientist Mike Weisend and his tDCS device | | 07:07 | Sally experiences time distortion and flow state during tDCS | | 08:34 | Weisend claims tDCS can “double the rate of learning” | | 10:15 | “This is not a scalpel. This is a sledgehammer.” | | 11:13–14:23| Jad tries tDCS live in studio, reports “state of flow” | | 15:28 | Scientist Peter Reiner on research limitations and small studies | | 16:28 | Exploration of the DIY tDCS community and safety concerns | | 18:45 | Risks of unintended effects—brain as an interconnected ecosystem | | 21:25 | Sally’s account of anxiety disappearance “for a couple of days” | | 24:33 | Sally likens the experience to a drug, expresses desire to repeat |

Conclusion

"9-Volt Nirvana" presents tDCS as a tantalizing interface between neuroscience, military applications, self-improvement, and even mood alteration. The episode captures the excitement, skepticism, and ambivalent ethics surrounding this technology. The personal stories and expert commentary bring the promise and peril of “brain juicing” into sharp relief: it might be possible to hack ourselves into better performance and blissful calm, but that path is rife with unknowns about efficacy, safety, and what it means for our sense of self.