Repetition suppression and plasticity in the human brain

The changing magnitude of the mismatch response over successive tone repetitions is considered to index the precision (certainty) of prediction error.

“Specifically, the changing magnitude of the mismatch response over successive tone repetitions (Figure 1A) is considered to index the precision (certainty) of prediction error. 4”

Neural circuits automatically learn and adapt to changing stimulus frequency.

“neural circuits automatically learn and adapt to changing stimulus frequency.”

This learning reflects short-term plasticity and can be achieved by iterative updating of top-down predictions by bottom-up prediction errors.

“This learning reflects short‐term plasticity and can be achieved by iterative updating of top–down predictions by bottom–up prediction errors. 4”

Six of the eight regions are based on prior studies that established a frontotemporal network responsible for generating the mismatch negativity response.

“Six of these regions are based on a series of prior studies of mismatch negativity generation with healthy adults and those with non‐AD dementia, 4 , 18 , 24 , 25 which established a frontotemporal network (primary auditory, superior temporal, and inferior frontal regions) responsible for generating the mismatch negativity response.”

The second set of models with both exponential and phasic change embody the hypothesis of predictive coding for sequential neural responses to stimuli.

“The second set of models with both exponential and phasic change embody the hypothesis of predictive coding for sequential neural responses to stimuli, allowing extrinsic connections to show stimulus‐specific adaptation with exponential decrease with repetition; while intrinsic connections show a phasic response, reducing after the deviant tone and recovering with subsequent tones thereby refle”

The winning model's combination of exponential and phasic basis functions is in line with a predictive coding framework for the mismatch negativity task rather than stimulus-specific adaptation only.

“in accordance with previous studies, 4 , 24 and in line with a predictive coding framework for the mismatch negativity task, rather than stimulus‐specific adaptation only. 4”

High precision 'surprise' in response to a deviant tone is followed by an initial reduction of precision, which gradually recovers as a new standard tone is learnt.

“As proposed by Garrido et al., 4 high precision “surprise” in response to a deviant tone is followed by an initial reduction of precision, which gradually recovers as a new standard tone is learnt.”