Today, Explained – "Is your brain lying to you?"

Vox – December 21, 2025

Episode Overview

This episode of Today, Explained explores how our brains interpret and sometimes distort sensory information—most notably, through the phenomenon of tinnitus (“ringing in the ears”). With the help of guest Noam Hassenfeld (from Vox’s Unexplainable), experts, and firsthand accounts, the hosts examine not only why we experience tinnitus, but how our perceptions are actively constructed by the brain, raising big questions about what’s “real” in our sensory experiences.

Key Discussion Points & Insights

1. What is Tinnitus?

• Definition and Manifestation:

  • Tinnitus is described as a persistent ringing or buzzing in the ears, which can range from mildly annoying to utterly debilitating (01:16–01:31).
  • For some, it's temporary (like after a loud concert); for others, it's a constant, high-pitched sound that impacts day-to-day life.

• Personal Story – Kelly’s Experience:

  • Listener Kelly developed tinnitus in her mid-twenties; at first, she thought it was the plumbing in her house since nobody else could hear the sound (02:11–03:01).
  • It worsened over time, affecting her social life and sleep:

    "It's like you're just trapped in a room with a crying kid. You can't stop crying or anything." — Kelly (03:26)

2. The Problem of Hidden Hearing Loss

• Normal Hearing Tests May Miss the Problem:

  • Kelly passed her audiology tests, leading to frustration and confusion (05:21).
  • Explanation: Standard hearing tests focus on the “soft sound” fibers, not those damaged by loud sounds. Damaged “loud sound” fibers (which won’t show up in typical tests) relate to what’s called “hidden hearing loss.”

    "The gold standard of hearing evaluation... is completely insensitive to the loss of those fibers." — Noam Hassenfeld quoting Stephane Maison (07:25)

• How It Connects to Tinnitus:

  • Damage to certain auditory nerve fibers leads the brain to "expect" input it isn't getting, which can result in the brain generating its own sounds (tinnitus).

3. The Brain’s Climate Control Analogy

• Self-Regulation Gone Awry:

  • The brain tries to maintain a “set point” for expected sensory input—like a thermostat keeping room temperature steady (08:03–08:20).
  • If auditory input is reduced (e.g., due to nerve fiber damage), the brain “turns up the volume” internally and creates phantom sound (tinnitus) to fill the gap.

    "It's kind of like turning on the heat, but it can't get the sound it needs, so it creates its own sound." — Noam Hassenfeld (08:36)

• Comparison to Phantom Limb:

  • Similar to phantom limb syndrome where missing limbs still seem to produce sensations, tinnitus is the brain creating sensations in the absence of actual stimuli (09:14).

4. Tinnitus as an Example of Brain “Superpower”

• Sensory Construction as Both Asset and Curse:

  • Our brain's tendency to “edit” and make sense of chaotic input is generally beneficial:
    • Example: The brain sculpts sound waves into comprehensible elements (words, bird songs, etc.) (13:21–14:17).

    "The world is just a big blob of sound and somehow our brain can pick out birdsong, word, car honk." — Noam Hassenfeld (13:21)

• Audio Illusions:

  • The "octave illusion": Even though both ears receive the same sequence of high and low notes, people perceive them as alternating between ears, illustrating how the brain edits raw data for clarity (14:38–15:59).

• Brain Training:

  • With enough practice or new sensory devices (like cochlear implants), people can re-train their brains to interpret sounds more accurately:

    "He practiced listening over and over again, and he retrained his brain so that it sounded less robotic and metallic." — Noam, on Mike Korast's adaptation to his cochlear implant (16:42–17:20).

5. Treatments & Coping with Tinnitus

• Masking (White Noise):

  • Some find relief by using noise to “mask” the ringing (white, pink, or brown noise), but this can backfire by directing attention to the tinnitus (18:05–18:55).
  • “One of the things that can actually make tinnitus worse is thinking about it.” — Hassenfeld (18:50)

• Mindfulness and Acceptance:

  • Gradually allowing the tinnitus to blend with other environmental sounds and not focusing on it is currently the best-available approach.

    “I’m actually just trying to take in all the sounds...just recognizing that sound, too.” — Kelly (19:35)

• No Quick Fixes:

  • Some researchers are experimenting with nerve growth proteins and retraining neural responses, but these are in early stages (17:34–18:05).

6. Perception: Hearing, Seeing, and Beyond

• Sensory Construction is Universal:

  • Discussion with Dr. Pascal Wallis (NYU neuroscientist):
    • The brain constructs realities for all senses: seeing faces in clouds (pareidolia), feeling itches that originate in the brain (neuropathic itch), etc. (23:58–24:32).
    • “You're seeing meaning everywhere. This is like man's search for meaning, basically, but in your brain.” — Wallis (24:28)

• The Blue/Gold Dress Phenomenon:

  • The infamous blue/black vs. white/gold dress: Perceptions differ based on personal experiences with light and daily routines, such as being a night owl (25:16–26:01).

    "Some people legitimately see as white and gold, some as black and blue. What we could show is it has to do with your assumptions about lighting." — Wallis (25:25)

• Language as Auditory Construction:

  • When learning a foreign language, the brain begins to insert (nonexistent) word boundaries, showing how our minds interpret ambiguous input (26:01–26:43).

7. Why Does the Brain Interpret Ambiguously?

• Survival, Not Accuracy:

  • The brain’s rapid, sometimes inaccurate interpretations serve survival: acting quickly is prioritized over precision (26:50–28:09).

    “If you were sitting around until you have all of the information...some other animal would have already eaten your lunch or maybe eaten you.” — Wallis (27:08)

• Reliability and Humility:

  • While our senses are reliable for navigating the world, everyone’s experience is slightly different—so we should remain humble about what we “know” (28:09–28:52).

8. Are We Living in the Matrix?

• Brains as Playwrights:

  • “It feels like our brains are just kind of putting on a play for us. We're not actually hearing the stuff that's out there. It's like the stuff that's out there is the script, and then our brain is reading the script for us and acting it out." — Noam Hassenfeld (20:31)

• Pascal’s Take:

  • Asked if we’re living in the Matrix, Dr. Wallis replies, “In all likelihood, yeah.” (28:56)

• A Deeper Reality:

  • Our perceptions are limited—they're the interface, not the whole reality.

    "We're sharing a low dimensional, three dimensional...embedding space. But there's a much deeper reality out there that our brain senses can't see." — Wallis (29:18)

Timestamps for Important Segments

• Tinnitus explained and Kelly’s story: 01:16–04:11
• Why standard hearing tests fail (hidden hearing loss): 05:21–07:32
• The brain’s “climate control” analogy for tinnitus: 08:03–09:14
• Phantom limb, the brain’s need to fill in missing data: 09:14–09:53
• Audio illusions, octave illusion, perception editing: 13:21–16:08
• Cochlear implant and retraining the brain: 16:15–17:28
• Current coping strategies for tinnitus: 17:34–19:35
• Seeing is also believing—visual perception tricks, “the dress”: 24:32–26:01
• Why the brain jumps to conclusions (survival): 26:50–28:09
• Philosophy: Are we in the Matrix? What is reality?: 28:52–29:45

Notable Quotes & Memorable Moments

• "I've grown so distant from my friends because with the lack of sleep, you're just not in any other mood for anybody." — Kelly (03:48)

• "That is a form of tinnitus. That's temporary tinnitus, and it usually goes away. But Kelly's tinnitus wasn't." — Jacqueline Glen Hill (04:39–04:48)

• "The gold standard of hearing evaluation...is completely insensitive to the loss of those fibers." — Noam Hassenfeld quoting Stephane Maison (07:25)

• "It's kind of like turning on the heat, but it can't get the sound it needs, so it creates its own sound." — Noam Hassenfeld (08:36)

• "Why would our brains do that to us?" — Jacqueline Glen Hill (09:53)

• "The world is just a big blob of sound and somehow our brain can pick out birdsong, word, car honk." — Noam Hassenfeld (13:21)

• "You’re seeing meaning everywhere. This is like man’s search for meaning, basically, but in your brain." — Pascal Wallis (24:28)

• "Your senses are not there for your viewing pleasure. It's there for survival." — Pascal Wallis (26:50)

• "It feels like our brains are just kind of putting on a play for us. We're not actually hearing the stuff that's out there." — Noam Hassenfeld (20:31)

• "In all likelihood, yeah." — Pascal Wallis, on whether we're living in the Matrix (28:56)

Final Reflections

• Sensory Perception is Actively Built: Hearing, sight, and all senses are subject to constant active interpretation and editing by the brain. This allows us to make quick decisions but also means our experience of reality is inherently subjective.

• We All See the World a Little Differently: From tinnitus to the color of “the dress,” assumptions, context, and personal history shape our every perception.

• Embrace Uncertainty and Curiosity: Accepting that our senses are just one version of reality can feel unsettling but also opens up a greater appreciation for both the power and limits of the human mind.

For more on how we interpret sound, check out the referenced Unexplainable series “The Sound Barrier.”