Large Brain Neuroscience in Elephants

• Applicant: Professor Dr. Michael Brecht
• Subject Area: Cognitive, Systems and Behavioural Neurobiology
• Term: since 2024
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 546068881

Contemporary cellular neuroscience is strong on small but weak on large brains. Here, we lay out a systemic agenda to analyze the elephant brain, one of the largest brains on the planet. Up to this point, we have only limited information about elephant cognitive capacities, brain structure, and neurophysiology. Technical advances and collaborations set up by our group pave the way to confront these issues: (i) We assembled the largest elephant brain collection worldwide. (ii) We set up collaborations with people studying elephants in the field. (iii) We set up behavioral experiments on the grasping behavior of zoo elephants. (iv) We trained elephants for non-invasive (EEG/EMG) physiological measurements. (v) We performed a high-resolution analysis of the musculature, innervation, and tactile sensors of the elephant trunk. (vi) We adapted established (histology; post-mortem MRI) and novel methods (synchrotron X-ray tomography; microCT/DiI-CT) to elephant brains. Given these advances, elephant neuroscience is ready for primetime. Preliminary findings and previous studies indicate that the cellular structure of elephant brains is markedly different from rodent brains and that elephants have haptic and cognitive abilities seen only in very few mammals. The neural control of elephant grasping is unique and based on the coarse control of thousands of muscles, which receive divergent input from motoneurons. This mode of control is very different from primate grasping, which is based on the fine control of a few dozen muscles, which receive massively convergent input from motoneurons. From neuroanatomy, we expect different muscle recruitment patterns in elephants than in primates, a hypothesis, which we will test with trunk EMG recordings. Our work will (i) make the elephant brain the best-studied very large brain (ii) develop methods for large brain analysis (iii) bridge between cellular and systems neuroscience of large brains.

• DFG Programme: Reinhart Koselleck Projects