Lactate supply overtakes glucose when neural computational and cognitive loads scale up
Yulia Dembitskaya1, Charlotte Piette1, Sylvie Perez1
1Dynamics and Pathophysiology of Neuronal Networks Team, Center for Interdisciplinary Research in Biology (CIRB), Collège de France, CNRS, INSERM, Université PSL, 75005 Paris, France.
Summary
Brain energy use for memory depends on task difficulty. Lactate fuels demanding neural computation and memory formation, while glucose supports simpler tasks, revealing distinct neuroenergetic roles.
Area of Science:
- Neuroscience
- Neuroenergetics
- Cognitive Science
Background:
- Neural computation and memory engram formation rely on energy supply.
- The specific roles of glucose and lactate in fueling different memory processes remain unclear.
Purpose of the Study:
- To investigate whether neuronal fueling by glucose or lactate differs with increasing neural computation and cognitive loads.
- To determine the differential engagement of glucose and lactate in supporting various forms of memory engram.
Main Methods:
- Electrophysiology
- Two-photon imaging
- Cognitive tasks (object-in-place, novel object recognition)
- Mathematical modeling
Main Results:
- Lactate supports high-stimulation load activity patterns and high attentional load tasks.
- Glucose is sufficient for less demanding neural computation and learning tasks.
- Lactate is mandatory for demanding neural computation (e.g., theta-burst stimulation) and high attentional cognitive tasks, while glucose suffices for lighter plasticity (e.g., spike timing-dependent plasticity).
Conclusions:
- Glucose and lactate metabolism are differentially engaged in neuronal fueling based on the complexity of activity-dependent plasticity and behavior.
- Lactate is crucial for high-demand cognitive functions and associated synaptic plasticity.
- Energy substrate allocation shifts from glucose to lactate with increasing neural and cognitive complexity.
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