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Amit Yaron @yaronamit.bsky.social · 10/07/2025

Our circuit model explains these results. Lateral interactions between prediction-error neurons cause unexpected tones to suppress neighboring predictions, sharpening each neuron's predictive field and making omission coding more precise and efficient.

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Amit Yaron @yaronamit.bsky.social · 10/07/2025

A key asymmetry reveals the mechanism: 📌 Receptive field: responds to both tones when heard 📌 Predictive field: fires only when one specific tone is omitted Same neuron — opposite selectivity for presence vs absence.

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Amit Yaron @yaronamit.bsky.social · 10/07/2025

This confidence built up over time: 🔹 Early in the sequence, gaps triggered little or no response 🔹 After repeated exposure to the target tone, the same gap evoked strong firing This suggests the brain gradually accumulates statistical regularities to form stable expectations.

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Amit Yaron @yaronamit.bsky.social · 10/07/2025

Omission responses tracked the target tone’s probability: 🔹 Gap in a sequence where the target tone was 90 % of items → strong firing 🔹 Gap in a sequence where the target tone was 10 % → weak or no firing This shows predictions are feature-specific and confidence-graded.

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Amit Yaron @yaronamit.bsky.social · 10/07/2025

These are “Probability-Encoding Omission Neurons” (PEONs) Their omission responses act as prediction error signals: The stronger the expectation for this specific tone, the stronger the firing when that tone fails to appear.

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Amit Yaron @yaronamit.bsky.social · 10/07/2025

Two-tone sequences were played with occasional silent gaps (5% omissions). Many of these neurons responded to both tones when present. ~13% also fired on gaps, but only when they occurred in a sequence dominated by one specific tone.

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Amit Yaron @yaronamit.bsky.social · 10/07/2025

New @plosbiology.org paper: doi.org/10.1371/jour... We found neurons in rat auditory cortex that signal narrow predictions for specific tones. Using omissions as a probe, we show that some neurons show frequency-specific expectations despite responding broadly to actual sounds. 🧵

doi.org

Auditory cortex neurons that encode negative prediction errors respond to omissions of sounds in a predictable sequence

Neurons encoding positive or negative prediction errors signal a mismatch between the expected and the experienced input. This study shows how neurons encoding negative prediction errors in the audito...

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Reposted by Amit Yaron

PLOS Biology @plosbiology.org · 19/06/2025

The sound of silence? @yaronamit.bsky.social &co show how #neurons encoding negative #PredictionErrors in the #AuditorySystem compute the omission of sounds in a predictable tone sequence (incl asymmetry between bottom-up receptive field & top-down predictive field @plosbiology.org 🧪 plos.io/4n61zeq

Left: Experimental design featuring eight conditions with two distinct tones (A and B) and a 5% omission rate, presented in random order. Each condition comprised 1,000 stimulus items, varying the probability of Tones A and B to achieve different predictability levels. Top right: Example of a neuron that responds to tones but not to omissions. The raster plot shows spikes (black dots) with time (ms) on the x-axis and trials on the y-axis. The PSTH displays firing rate over time, with tone stimuli (blue shading) and omissions (gray shading). The black line represents the firing rate, the red line shows omission responses, and the green line indicates the omission baseline. Bottom right: Example of a neuron that selectively responds to the omission of specific tones. The same representation is used as in top right.

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