Mapping the relay and higher-order thalamic nuclei functional interactions with the large-scale cortical functional networks

The thalamus acts as a central communications hub for the brain, relaying information from the senses and cortico-cortical interactions. The cortex heavily relies on thalamic nuclei interactions for most of its functional processing. Despite this, human thalamic nuclei's detailed functional interactions and behavioral association with the cerebral cortex remain partially uncharted. Therefore, the study investigated the functional interactions and their behavioral association between thalamic nuclei and the large-scale cortical functional networks. Specifically how different parts of the thalamus are associated with various mental tasks.

The research expands the understanding of thalamic-cortical interactions by examining network-specific connectivity and task-related topical mapping of cortical areas with the thalamus. The study utilizes 3.5 million functional brain scans of 730 subjects and summarized topic maps from 14,371 task-fMRI studies. The research identifies that relay and higher-order thalamic nuclei have intertwined functional associations with various cortical networks. Notably, relay-specific thalamic nuclei suggest participation not only in relay-specific behavior but also in higher-order functions. Moreover, the study indicates that the thalamus nuclei seem to operate similarly to a central processing unit in a computer, displaying functional multiplicity where many of its subunits share tasks. In essence, this research sheds light on the intricate operations of the thalamus, enhancing our comprehension of its multifaceted interactions with the cortex and offering avenues for clinical and neuroscience research.