Friday, Jun 27: 11:30 AM - 12:45 PM
Oral Sessions
Brisbane Convention & Exhibition Centre
Room: M1 & M2 (Mezzanine Level)
Suggested title: Neuroanatomy, Metabolism, and Neurotransmission in the Human and Primate Brain
Presentations
Muscle sympathetic nerve activity (MSNA) is composed of bursts of action potentials generated by muscle vasoconstrictor neurones that supply arterioles in skeletal muscles. MSNA is tightly coupled to the cardiac cycle via the arterial baroreflex, and by controlling blood flow to muscle, contributes importantly to the beat-to-beat regulation of blood pressure through variations in arteriolar diameter. MSNA originates within a nucleus of the brainstem - the rostral ventrolateral medulla (RVLM). Using MSNA-coupled functional MRI (fMRI) (Macefield, 2010) - in which we record MSNA and perform fMRI simultaneously, we can exploit the higher spatial resolution and signal-to-noise found at ultra-high field 7 Tesla. We aim to functionally identify the brainstem nuclei responsible for generating sympathetic drive using high-resolution 7T fMRI coupled with direct recordings of MSNA
Presenter
Rebecca Glarin, University of Melbourne Melbourne, Victoria
Australia
Glucose is the primary fuel of the human brain, and its metabolism is tightly regulated on a cellular level. Neurons and glial cells, including astrocytes (Ast), microglia (Mic), and oligodendrocytes (Oli), distribute heterogeneously across the brain and possess divergent metabolic profiles [1]. These metabolic profiles have not been studied in the human brain. Metabolic differences within the cell types emerge from differential gene expressions. We leveraged transcriptomic data of post-mortem brains from the Allen Human Brain Atlas (AHBA) to characterize the metabolic profiles of brain cells and investigate their expression patterns across the human cortex and subcortex [2].
Epilepsy is one of the most common neurological conditions worldwide. Although many epileptic patients improve with anti-seizure medication, up to 40% of them are drug-resistant (Engel, 2016). For these patients, the most successful treatment is epilepsy surgery, whereby the region giving rise to seizures is removed. Non-invasive techniques such as magnetic resonance imaging (MRI) are key to identifying the surgical target and ensuring a seizure-free future in drug-resistant patients. Where conventional MRI is inconclusive, patients need to undergo intracranial electroencephalography (iEEG), an invasive procedure not without risk of complication, that offers restricted spatial sampling. While whole-brain structural and functional alterations have been widely studied in the epileptic brain using a tandem iEEG-MRI approach, finer-scale local alterations have yet to be assessed.
Presenter
Yigu Zhou, Montréal Neurological Institute Montréal, Québec
Canada
Brain aging involves multiple degenerative processes, including glucose hypometabolism, atrophy, and cerebrovascular disease. While these manifestations often become detectable only in later stages, neuroimaging-based biomarkers can identify changes decades earlier. Previous research indicates that brain networks undergo substantial reorganization starting in the late 40s, with patterns similar to those observed in Type 2 diabetes mellitus, suggesting neuronal insulin resistance as a potential mechanism. While glucose is the brain's primary fuel, ketones provide an alternative that can be metabolized by neurons without insulin and thus bypass insulin resistance. This study integrates lifespan brain-aging trajectory, mechanistic, and interventional findings to distinguish earlier catalyzing processes from later downstream effects.
White matter connections coordinate functional brain activity by interconnecting various brain regions, weaving together a complex pattern with functional specializations refined throughout ontogeny and phylogeny (Thiebaut de Schotten & Forkel, 2022). Comparative analysis of white matter connections including a broader range of species could provide valuable insights into the mechanisms involved in human-specific cognitive functions. As a highly vocal Platyrrhine monkey that shares key anatomical and functional features with humans, marmosets provide a unique opportunity to chart white matter tracts for investigating brain evolution in the primate lineage.
Presenter
Yufan Wang, Institute of Automation, Chinese Academy of Science Beijing, China
China
The cortical and laminar distribution of neurotransmitter receptors is vital for brain function, yet the mechanisms for this remain poorly understood. High-resolution imaging of receptors is feasible only through ex vivo techniques like 2D autoradiography. We developed a 3D reconstruction algorithm, BrainBuilder[1], and used it to create 12 neurotransmitter receptor atlases for the macaque brain at 0.25mm³ resolution. Laminar receptor distributions from these atlases were compared with fMRI activation maps[2] and functional networks[3] to elucidate the role of neurotransmitters in brain function.
Presenter
Thomas Funck, Child Mind Institute Montréal, QC
Canada