Light genetics functional magnetic resonance imaging (fMRI)
Light genetics fMRI activation regions may have high targeting property.The specificity of what advantage?
Light genetics fMRI capture highly specific brain activation region is light modulation region launched the neural activity will spread to the downstream targets.The specificity is determined by many factors, these factors include:i.) virus express genetic modulation design paradigm, light, and the response characteristics of the local cluster of neurons;II) initiated by the strength of the neural activity and time characteristics;III.Genetics) light disturbance during occur at multiple scales of spontaneous activity;IV) stimulation sites and downstream target connection structure of directness, density and driver/modulation characteristics;V) stimulation sites and the dynamics of the functional connectivity between the downstream target, as wellVI) fMRI data collection (that is, the system, set up and order, etc.) and the analysis method.Light genetics fMRI can through a cell type specific, precise time and space, the reversible nerve activity of start/manipulation, at the same time using the multi-function imaging design for large-scale visual reaction, the precise control of experiment combined with flexible data display, help the various characteristics of long distance function circuits/network and mass space-time coordination of neural activity.
Although some neurons in neural network range is very small, but the light of the specific genetic reaction whole brain stimulation could induce.We found that the reaction can be in what time points, and how does them?
The brain is a special biological information processing system, is composed of many neurons cluster, the cluster to connect to the specific functions of neurons circuits and networks.During the current task or rest, the brain through the local circuit and/or the whole brain network, coordinate various neural activity of different time and space scales, to perform a variety of functions.Through appropriate stimulating neurons clusters show whole brain long distance projection, or start to spread in the whole brain low-frequency activity, it can display the whole brain response.Reaction can reflect the whole brain is stimulated neurons clusters or multiple downstream target site neural activity to raise.In a state of dynamic global brain switch, whole brain function selectivity modulation of network communication, distributed information storage and organization of door control and so on, the whole brain reaction plays an important role.
Whether certain fMRI study hard or cannot use normal stimulation method and carry out?
At present, the method of ordinary light stimulation, cannot simulate the multi-sensory experience environment or the natural scenery of the subjects' brains.Because the resolution is limited by submillimeter level of fiber diameter, so it is difficult to perform multiple site operation, also is unable to realize accurate light disturbance for single cell level.Common use of repetition of the design also limits the light pulse exciting stimulus paradigm in check cases caused by nature genetics fMRI study more physiological reaction.At the same time, in view of the closed loop stimulation of neurons cluster, we need a millisecond time resolution, real-time monitoring of local neuronal activity, in order to determine the dynamic state of local cluster of neurons or network, but it is hard to done through ordinary stimulation method.
Before light genetics fMRI is primarily a clinical technique.By using the method of research into the clinical relevance?
The light of the health control group genetics fMRI research results can help us to improve understanding of the normal brain works, and promote the development of clinical application of fMRI/neuroimaging methods.At the same time, the normal model and disease model between light genetic differences in fMRI results may guide us to develop our diagnostic technique, and to clarify the underlying mechanisms of the disease.In addition, in view of the model for the light of genetics fMRI research results can be used to guide the development of intervention treatment plan.
We still need to walk far to from cellular level understanding of the neural network operation system?
At present, the fMRI is unable to realize spatial resolution cell level, however, in the next few years, using a variety of technical development, we will be able to check neural network from the cell level.First of all, through the use of advanced multi-function genetic tools, and combined with fMRI to cell level control circuits, we begin to get from the cell level an excellent chance to check the results of neural network disturbance.Secondly, through the cell level resolution optical imaging combined with light genetics fMRI, will help deepen our understanding of cellular neural network.Third, with precision genetics stimulus method (for example, holographic) recently and sustainable development, we will be able to realize cell stage light stimulation, at the same time through the whole brain fMRI, make corresponding results visualization.
The brain is a special biological information processing system.
We will be able to realize cell stage light stimulation, at the same time through the whole brain fMRI imaging, the corresponding results visualization.
Professor Wu Xuekui
Dr. Wu is the Hong Kong university biomedical engineering professor and dean of the life.In 1984 he received his bachelor's degree in electrical engineering at tianjin university, 1988 master's degree in medical physics from the university of Wisconsin, Madison, and in 1993 received a doctor's degree in radiation science at the university of California, irvine.From 1990 to 2003, Dr. Wu at Columbia University in New York, served as assistant professor, and radiation and associate professor of biomedical engineering.Dr. Wu to join the university of Hong Kong in 2003.His research interests include nuclear magnetic resonance (NMR) biophysics, reconstruction algorithm, advanced biomedical applications and barrier-free medical systems engineering (Hk/bislab/www4. The city.).Currently, he is one of the major research emphasis through the function, diffusion MRI and electrophysiology, and spectral behavior assessment and neural control method (for example, light genetics), the combination of developing the most advanced method of functional magnetic resonance imaging (MRI) to detect brain circuits and functions in rodent models.Dr. Wu is a member of ISMRM, IEEE and AIMBE academicians.Since 2011, was a member of the biology medical nuclear magnetic resonance (NMR), Dr. Wu (NBM) Asia Pacific editor.