Short Wave — "The Mystery Of Inner Monologues" (November 19, 2025)

Episode Overview

In this episode of Short Wave, hosts Emily Kwong and Rachel Carlson dive into the science and lived experience behind inner monologues—those streams of verbal thought that play (or, for some, don't play) in people's heads. Prompted by Emily's revelation that she doesn't have an inner monologue, the hosts investigate how common this is, how inner speech develops, what brain science reveals, and why the diversity of inner experiences matters. Psychologists Russell Hurlburt (University of Nevada) and Charles Ferniho (Durham University) join to explain the history, methods, and neural basis of inner speech, as well as the relationship between inner monologue, voice hearing, and mental health.

Key Discussion Points & Insights

1. Not Everyone Has an Inner Monologue

• Emily’s Confession: Emily reveals she doesn't have an inner monologue, instead experiencing her thoughts as images and feelings.
  • "My inner experience isn't really word based. It's more like a moving landscape of images. It's kind of like soaking in an emotional bath."
    — Emily Kwong (01:14)
• Variety of Experiences: Rachel, in contrast, has a "loud," dialogue-heavy inner monologue, often imagining conversations or scripts playing out in her mind.
  • "Mine is loud. Oh no, it does not feel like a bath. It feels like it's dialogue heavy... It's a screenplay."
    — Rachel Carlson (01:34)
• Listener Curiosity: Audience emails express disbelief and curiosity (“Is that even a thing?”). The hosts confirm that science backs up this diversity.

2. Studying Inner Experience: Descriptive Experience Sampling (DES)

• Introducing Russell Hurlburt: Pioneering psychologist who sought to study inner experience.
  • "People didn’t know what they were talking about when they picked a number on a Likert scale... The data was just rotten on the way in."
    — Russell Hurlburt (02:35)
• The Beeper Study: Instead of surveys, Hurlburt used a “beeper” method, prompting people to jot down what was happening in their minds at random moments. This descriptive approach proved more revealing but still had limitations.
• Limits of Self-Report:
  • "You've got no good reason to be confident that you do or do not have an inner monologue because there's just too many layers between what your inner experience actually is and what you might say about it."
    — Russell Hurlburt (03:18)

3. The Science of Inner Speech

• Charles Ferniho’s Research: Ferniho studies how inner speech develops and its neural underpinnings.
  • "We've shown you can do it... you can have a science of it."
    — Charles Ferniho (03:49)
• Origins in Childhood: Inner speech develops from "private speech"—children talking to themselves as they learn, which gradually internalizes.
  • "When kids are talking to themselves out loud, we call that private speech. And the idea is that it's the precursor... So the inner speech that you and I probably experience... comes from developmentally from private speech."
    — Charles Ferniho (05:43)
  • This idea originated with Russian psychologist Lev Vygotsky.

4. What’s Happening in the Brain?

• Language Areas: Key language regions—Broca’s area (frontal, speech production) and Wernicke’s area (temporal, speech comprehension)—are both involved.
  • "Those two areas create a kind of resonating loop which always shows up when we ask people to speak to themselves or out loud in the scanner."
    — Charles Ferniho (07:02)
• More Than Language: Inner speech, especially dialogic forms (imagined conversations), involves additional brain regions—like those used in representing other people’s minds.

5. Scanning the Inner Voice: Elicited vs. Spontaneous Inner Speech

• Experimental Findings: Using both DES and fMRI, Ferniho and Hurlburt found that "elicited" (prompted) inner speech and naturally occurring ("spontaneous") inner speech activate the brain differently.
  • "When we had elicited inner speech, there was lots of that Broca’s area... But when people were doing inner speech spontaneously, there was much less of time... more of that region a bit further back, the Wernicke’s area."
    — Charles Ferniho (09:21-10:23)
• Caution for Neuroscientists:
  • "We shouldn’t assume that when you put somebody in the scanner and tell them to do something, the thing that results is anything like the thing you’re actually interested in."
    — Charles Ferniho (10:28)

6. Voice Hearing: Science and Stigma

• What Is Voice Hearing? Experiencing a voice with no external source, often associated with mental illness but found in many healthy individuals too.
  • "What we've learned is that this experience happens to all sorts of people in all sorts of walks of life... There are a significant number of people who hear voices, who are not distressed by them... find them useful, creative, guiding."
    — Charles Ferniho (11:21)
• Neuroscientific Theory: Voice hearing may result from inner speech being misattributed to an external source when a brain signal (from Broca’s to Wernicke’s) fails to indicate ‘it’s just you.’
  • "Usually when you're speaking, that bit at the front sends a little internal message... In the case of voice hearing, that message doesn't get through."
    — Charles Ferniho (13:09)

7. Diversity of Inner Worlds & Mental Health

• Some People Have None: The researchers stress that some people almost never use inner speech but have rich mental imagery, music, or emotions.
• Should We Cultivate Inner Speech? Ferniho emphasizes celebrating the diversity of minds, rather than suggesting everyone should have or develop inner speech.
  • "I'd like to celebrate the diversity of human minds. I think we are so different... I wouldn't ever want to set out and say to people that they should improve their inner speech..."
    — Charles Ferniho (13:52)
  • "Sometimes inner speech can have a negative side... If that's bothering you, there are maybe things that you can do to rethink it."
    — Charles Ferniho (14:14)
• Resources: Ferniho recommends understandingvoices.com for more on voice hearing.

Notable Quotes & Moments with Timestamps

• Emily on her non-verbal inner world:
  • "It's kind of like soaking in an emotional bath." (01:14)
• Rachel on her verbal mind:
  • "Mine is loud... Dialogue heavy... It's a screenplay." (01:34)
• Russell Hurlburt’s humility:
  • "You’ve got no good reason to be confident that you do or do not have an inner monologue..." (03:18)
• Charles Ferniho on Vygotsky & development:
  • "That is the theory of a great Russian psychologist called Lev Vygotsky..." (06:35)
• Caution about brain studies:
  • "We shouldn’t assume that when you put somebody in the scanner... the thing that results is anything like the thing you’re actually interested in." (10:28)
• Diversity celebration:
  • "I think it's wonderful that there is this diversity and we can celebrate that diversity." (13:59)

Key Timestamps

• 00:34–01:32: Emily reveals she lacks an inner monologue; audience intrigue.
• 02:03–03:35: Origins of inner monologue research; limits of surveys and self-knowledge.
• 05:20–06:20: How inner speech arises from childhood private speech (Vygotsky).
• 07:02–08:24: Brain areas involved in inner speech (Broca’s, Wernicke’s, and beyond).
• 09:13–10:55: How imaging studies complicated (and sometimes clarified) our understanding.
• 11:09–13:15: The science and experience of "voice hearing" and its misunderstood diversity.
• 13:52–14:51: On the value of inner diversity and healthy approaches to inner speech.

Conclusion

The episode highlights the complexity and diversity of human inner life, dismantling the myth that everyone hears an inner voice. Science is only beginning to map what we experience inside, and, as Ferniho stresses, the real takeaway is to celebrate the many forms our minds can take—whether filled with dialogue, images, music, or silence. If your inner monologue is distressing (or missing), you're simply part of the grand variety of the human mind. For more, Ferniho recommends understandingvoices.com.

For Listeners:

Skip to:

• 01:14 for Emily's inner "bath"
• 02:03 for the history of inner experience studies
• 05:30 for how children develop inner monologue
• 09:13 for brain imaging findings
• 11:09 for the connection to voice hearing
• 13:52 for why not having (or having!) an inner monologue is just one way to be human

Short Wave makes complex neuroscience and psychology not just accessible, but warmly human.