Many methods of exploration are available to scientists to better understand the brain and how it works. A brief overview of the techniques used at Paris Brain Institute.
Electrophysiology
Electrophysiology allows the recording of electrical signals (nervous influx or action potential) emitted by neurons to communicate with each other. Understanding how the brain functions under normal conditions is essential to understand and better treat the impaired functions in diseases of the nervous system, but also to preserve it in its normal state. The electrical signal transmitted by each neuron after activation is a key component of brain activity that is altered in neurological and psychiatric disease and is often the cause of the observed deficits.
Altered action potential is, for example, the starting point for epilepsy. Some research at Paris Brain Institute, for example, focuses on exploring extreme brain conditions that express continuous and abnormal electrical activities.
Neuroimaging
Advances in neuroimaging in recent decades have led to a considerable increase in knowledge about the anatomy and functioning of the nervous system. Neuroimaging techniques are grouped into two main categories:
- Neurophysiological techniques based on the measurement of electrical or magnetic activity of brain cells, such as electroencephalography (EEG) and magnetoencephalography (MEG).
- Techniques that indirectly measure changes in brain activity through changes in brain perfusion or by injecting radioactive molecules, such as magnetic resonance imaging (MRI) and positron emission tomography (PET).
Neuroimaging research at Paris Brain Institute focuses on three main areas:
- Clinical research: study of major diseases of the nervous system and development of innovative treatments;
- Research in the cognitive sciences: understanding how the brain works and studying the neural bases of thought, behaviour and ageing;
- Signal and image processing research: development of new methods for acquiring and processing activity ́ and brain imaging data.
Magnetoencephalography
Molecular and Cellular Approaches
Molecular and cellular approaches are used to understand the genetic, molecular and cellular basis of central nervous system development, function and disease. These include:
- Genetic sequencing, the reading of the long DNA molecules that make up chromosomes. This reading makes it possible to analyse the genome, detect possible mutations in genes and identify possible associations between these mutations and the manifestation of neurological diseases.
- Cellular explorations by setting up easily manipulable cell cultures to reproduce, in a simplified way, the mechanisms of nerve pathologies. This work requires recording the activity of neuronal cells in order to assess possible defects in the transmission of the electrical signal, and manipulating "stem" cells made pluripotent to produce authentic nerve or glial cells. When examining the functioning or dysfunction of the brain as a whole, tissue-sectioned histology techniques are used to assess the integrity of neuron and glial cell populations within different brain regions. The visualization of brain structures can also be done in 3D, on brain tissue made transparent by a technique known as clarification.
- Cell imaging, to observe at the microscopic scale molecules, cells and tissue sections, cellular movements or even compartments within cells (organelles, viruses, crystals, molecules).
Study of the brain using artificial intelligence
Paris Brain Institute is working to develop new mathematical and computational approaches to the study of the structure of the human brain and its functional networks. The need to transform raw imaging data into formalized models such as geometric models of brain structure, statistical models of populations, connectivity graphs is now essential for defining new pathology biomarkers, studying the correlations between genetics and symptoms, and characterizing the functional responses of the brain.
