Description: The thalamus plays a central role in brain function, acting as a hub for sensory relay, information integration, and higher cognitive processes. It is increasingly recognized as a key structure affected in neurodevelopmental disorders such as schizophrenia and in individuals born preterm. My talk will explore how thalamic structure - particularly its distinct nuclei - differs across these populations, and how we are moving beyond group-level comparisons toward individualized analyses using normative modeling. In preterm-born adults, we found a global reduction in the volume of all thalamic nuclei, pointing to widespread disruption of thalamocortical development (Thalhammer, Nimpal, et al., 2024). In contrast, individuals across the schizophrenia spectrum exhibit selective volume reductions, particularly in medial and lateral thalamic nuclei. These reductions are already evident in clinical high-risk and first-episode psychosis groups, suggesting early and targeted involvement of specific thalamocortical pathways (Thalhammer, Schulz, et al., 2024). However, increasing evidence suggests that not only behavioral but also neuroanatomical profiles are tremendously heterogeneous between individuals with neurodevelopmental disorders (Di Biase et al., 2022; Dimitrova et al., 2021; Lv et al., 2021; Thalhammer, Seidlitz, et al., 2024). I will end with interesting preliminary results about a recent ENIGMA study: using normative modeling applied to a large cohort of patients with schizophrenia (n=1,193), we showed that fewer than 10 % show volume deviations in any given thalamic nucleus. Additionally, structural covariance analyses revealed significant network-level disruptions in schizophrenia: only patients, not controls, exhibit significant covariance between thalamic and cortical surface area deviations. These alterations of covariance patterns might be partly explained by regional schizophrenia risk gene expression. Together, my work aims at a shift toward a more individualized and nuclei-based investigation of thalamic abnormalities in neurodevelopmental disorders to advance understanding of developmental origins and genetic underpinnings.
Presenters: Melissa Thalhammer, Technical University of Munich