SlimeMoldTimeMold (SMTM) recently finished a 13-part series on psychology, “The Mind in the Wheel”, centering on feedback loops (“cybernetics”) as kind of a grand unified theory of the brain.

There are parts of their framework I like—in particular, I think there are innate drives (pain is bad, eating-when-hungry is good, etc.), and I think that the top priority of neuroscience & psychology should be to figure out exactly what they are and how they work.

Just kidding! Control theory is great. I’m all for it. …I just don’t think it's a grand unified theory of the brain. (source)

But when we drill into details, I have lots of disagreements with SMTM's account.

I think there's a general failure mode of “grand unified theories of the brain”: the brain needn’t have any grand unified theory in the first place. I find that people with such theories are often doing the thing [...]

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Outline:

(02:41) 0. PROLOGUE - EVERYBODY WANTS A ROCK

(03:17) 1. PART I - THERMOSTAT

(03:47) 1.1 Feedback is broader than the setpoint + comparator thing

(05:44) 1.2 Emotions do not correspond to error signals in homeostatic feedback loops

(07:01) 1.3 Happiness does not correspond to correcting error signals

(07:46) 1.4 Pleasure does not really correspond to correcting error signals either

(09:46) 1.5 My picture

(14:25) 2. PART II - MOTIVATION

(14:50) 2.1 Do governors vote for different voluntary actions?

(15:23) 2.2 Is there a gate that stops votes below a minimum threshold?

(16:54) 2.3 How do we think about executive function and self-control?

(18:20) 2.4 Is suffering good when it's under your control?

(19:32) 3. PART III - PERSONALITY AND INDIVIDUAL DIFFERENCES

(20:04) 4. PART IV - LEARNING

(23:25) 5. PART V - DEPRESSION AND OTHER DIAGNOSES

(25:40) 6. PART VI - CONFLICT AND OSCILLATION

(26:46) 7. PART VII - NO REALLY, SERIOUSLY, WHAT IS GOING ON?

(27:34) 71/2. INTERLUDE - I LOVE YOU FOR PSYCHOLOGICAL REASONS

(28:37) 8. PART VIII - ARTIFICIAL INTELLIGENCE

(34:37) 8.1 Do humans do instrumental convergence stuff?

(36:37) 9. PART IX - ANIMAL WELFARE

(37:01) 10. PART X - DYNAMIC METHODS

(41:13) 11. PART XI - OTHER METHODS

(41:23) 12. PART XII - HELP WANTED

The original text contained 4 footnotes which were omitted from this narration.

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First published:
May 14th, 2025

Source:
https://www.lesswrong.com/posts/LfqFZvfSQhnCXHFE6/re-smtm-negative-feedback-on-negative-feedback

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Narrated by TYPE III AUDIO.

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Images from the article:

Just kidding! Control theory is great. I’m all for it. …I just don’t think it’s a grand unified theory of the brain. (source __T3A_LINK_IN_POST__)

My (mildly oversimplified) sketch of how homeostatic feedback control loops work in the brain. See text.

Apple Podcasts and Spotify do not show images in the episode description. Try Pocket Casts, or another podcast app.

“Re SMTM: negative feedback on negative feedback” by Steven Byrnes

LessWrong (30+ Karma)