Neural representation during associative threat learning in pulvinar divisions, MD, and LGN.

(a) Human fear conditioning paradigm during fMRI. (b–d) Means ± SE of activation in response to CS+ vs. CS− at both block-wise and trial-wise levels within pulvinar divisions (b), MD (c), and LGN (d). Block-level comparisons were assessed using paired t-tests, while trial-level effects were examined using a 2 × 2 repeated-measures ANOVA, followed by post hoc comparisons between CS+ and CS− across the four trials. Multiple comparisons were controlled using false discovery rate (FDR) correction. Conditioning sample size: n = 293. Detailed statistical parameters are provided in Supplementary Tables 1–2. Additionally, cross-validation analyses were conducted to assess the robustness of the CS+ vs. CS− signal in the anterior pulvinar and MD, consistent with our interpretation of learning-related effects (Supplementary Figs. 1–2 and Supplementary File 1). *p < 0.05, **p < 0.01, ***p < 0.001. SE, standard error; MD, mediodorsal thalamus; LGN, lateral geniculate nucleus; CS+, conditioned stimulus predicting shock; CS−, conditioned stimulus predicting no shock. Display items in panel (a) were created using BioRender.

Quantifying the relationships between the anterior pulvinar and MD during conditioning.

a. Hierarchical regression models of trial-wise relationships between the anterior pulvinar and MD activations while controlling for a potential effect of anatomical proximity. The effect of anatomical proximity was controlled by progressively adding other pulvinar divisions as controls. b. Results of a hierarchical model that included the LGN as an alternative control, distinct from the pulvinar. c. Comparison of activation levels in the anterior pulvinar and MD at both block-wise and trial-wise levels (means ± SE). Sample size in these analyses: n = 293. Supplementary analyses testing alternative hypotheses regarding the correlations between the MD and all pulvinar divisions are presented in Supplementary Fig. 3. *p<0.05, **p<0.01, ***p<0.001 MD: Mediodorsal thalamus. LGN: Lateral geniculate nucleus. SE: Standard error.

A data-driven approach to understanding the functional relationships between pulvinar divisions during conditioning.

a. Means ± SE of activation differences between pulvinar divisions. b. Network analysis reveals that the medial pulvinar serves as a central hub, mediating interactions among pulvinar divisions and exhibiting increased centrality measures. c. Schematic visualization of activation patterns we observed in pulvinar divisions. d. Previous studies suggest that the inferior and lateral pulvinar are involved in processing basic visual information (Berman and Wurtz, 2010, 2008; Cortes et al., 2024), while the medial pulvinar is associated with higher-level functions, including working memory (Homman-Ludiye and Bourne, 2019). e. Based on b-d, we hypothesize that the medial pulvinar mediates the relationships with other divisions. f. Mediation analysis supports our hypothesis (panel e). g. Validation of the mediation model on an additional independent sample. Dashed paths in panels f and g represent statistically unstable paths, while the continuous paths indicate stable paths. *p<0.05, **p<0.01, ***p<0.001 SE: Standard error. SC: Superior colliculus. Display items in panels d and e were created using BioRender. Note: The functional relationships among pulvinar divisions during threat learning should be interpreted as computational dependencies derived from statistical associations. These effects may reflect indirect interactions mediated by corticothalamic and thalamocortical pathways (e.g., via visual cortex), rather than direct inter-nuclear connectivity. Elucidating the underlying anatomical mechanisms will require future studies.

Neural representation during extinction learning in pulvinar divisions, MD, and LGN.

(a) Human extinction learning paradigm during fMRI. (b–d) Means ± SE of activation in response to CS+ vs. CS− at both block-wise and trial-wise levels within pulvinar divisions (b), MD (c), and LGN (d). Block-level comparisons were assessed using paired t-tests, while trial-level effects were examined using a 2 × 2 repeated-measures ANOVA, followed by post hoc comparisons between CS+ and CS− across the four trials. Multiple comparisons were controlled using false discovery rate (FDR) correction. Extinction sample size: n = 320. Detailed statistical parameters are provided in Supplementary Tables 4–5. *p < 0.05, **p < 0.01, ***p < 0.001. SE, standard error; MD, mediodorsal thalamus; LGN, lateral geniculate nucleus; Extinguished CS+, conditioned stimulus that no longer predicts shock; CS−, conditioned stimulus predicting no shock. Display items in panel (a) were created using BioRender.

Neural representation during extinction recall in pulvinar divisions, MD, and LGN.

(a) Human extinction recall paradigm in the fMRI conducted within safe contextual cues. (b–d) Means ± SE of activation in response to CS+ vs. CS− at both block-wise and trial-wise levels within pulvinar divisions (b), MD (c), and LGN (d). Block-level comparisons were assessed using paired t-tests, while trial-level effects were examined using a 2 × 2 repeated-measures ANOVA, followed by post hoc comparisons between CS+ and CS− across the four trials. Multiple comparisons were controlled using false discovery rate (FDR) correction. Extinction recall sample size: n = 412. Detailed statistical parameters are provided in Supplementary Tables 6–7. *p < 0.05, **p < 0.01, ***p < 0.001. SE, standard error; MD, mediodorsal thalamus; LGN, lateral geniculate nucleus; Extinguished CS+, conditioned stimulus that no longer predicts shock; CS−, conditioned stimulus predicting no shock. Display items in panel (a) were created using BioRender.

Neural representation during threat renewal in pulvinar divisions, MD, and LGN.

(a) Human threat renewal paradigm in the fMRI conducted within threat contextual cues in the original context where fear conditioning occurred. (b–d) Means ± SE of activation in response to CS+ vs. CS− at both block-wise and trial-wise levels within pulvinar divisions (b), MD (c), and LGN (d). Block-level comparisons were assessed using paired t-tests, while trial-level effects were examined using a 2 × 2 repeated-measures ANOVA, followed by post hoc comparisons between CS+ and CS− across the four trials. Multiple comparisons were controlled using false discovery rate (FDR) correction. Threat renewal sample size: n = 318. Detailed statistical parameters are provided in Supplementary Tables 8–9. *p < 0.05, **p < 0.01, ***p < 0.001. SE, standard error; MD, mediodorsal thalamus; LGN, lateral geniculate nucleus; Extinguished CS+, conditioned stimulus that no longer predicts shock; CS−, conditioned stimulus predicting no shock. Display items in panel (a) were created using BioRender.

Task-related thalamic connectivity with threat-related brain regions.

(a–d) Thalamic seed-to-ROI connectivity with the vmPFC, sgACC, dACC, amygdala, and hippocampus during conditioning (n = 293), extinction (n = 320), recall (n = 412), and renewal (n = 318). Red lines indicate significant positive connectivity for CS+ vs. CS− following FDR correction across regions (pFDR < 0.05); gray lines indicate non-significant effects. For each panel, boxplots and kernel density estimates show the distribution of connectivity values for CS+ and CS−. All thalamic regions of interest—including pulvinar divisions (anterior, inferior, lateral, medial), LGN, and MD—were analyzed using identical statistical procedures. To maintain figure clarity and focus on effects relevant to the main conclusions, we display only seeds showing at least one significant CS+ vs. CS− differences after FDR correction. Non-significant seeds did not show systematic condition-related differences. *p < 0.05, **p < 0.01. MD, mediodorsal thalamus; LGN, lateral geniculate nucleus; vmPFC, ventromedial prefrontal cortex; sgACC, subgenual anterior cingulate cortex; dACC, dorsal anterior cingulate cortex; CS+, conditioned stimulus predicting shock; CS−, conditioned stimulus predicting no shock. gPPI; generalized psychophysiological interaction; connectivity values are Fisher z–transformed correlation coefficients.

Neurobehavioral models of thalamic involvement in associative threat learning and memory.

a. Schematic illustration of thalamic circuitry during the acquisition of associative threat learning, highlighting interactions between pulvinar divisions, MD, and LGN with key brain regions involved in fear expression. b. A thalamic-dependent “toggle switch” regulates the retrieval of safety vs. threat-related memory. The MD-dACC connectivity modulates the interaction between dACC and vmPFC, promoting vmPFC dominance during extinction recall. In contrast, the anterior pulvinar-vmPFC connectivity promotes dACC dominance, enhancing the expression of threat memory during threat renewal. MD: Mediodorsal thalamus. LGN: Lateral geniculate nucleus. vmPFC = Ventromedial prefrontal cortex. dACC = Dorsal anterior cingulate cortex. V1, V2, and V4: Primary, secondary, and fourth visual areas. TEO, TE: Temporal cortex regions. Hypo.: Hypothalamus. Hippo.: Hippocampus. Created using BioRender. Note (panel a): Known pulvinar–cortical connections, as well as sensory input pathways (e.g., visual inputs via the retina/LGN and nociceptive inputs via the spinothalamic tract), are not explicitly shown. These connections are well established anatomically but were omitted due to their heterogeneity and incomplete characterization at the level of pulvinar subnuclei. Their absence should not be interpreted as a lack of anatomical or functional relevance.