Optogenetics, experimental method in biological research involving the combination of optics and genetics in technologies that are designed to control (by eliciting or inhibiting) well-defined events in cells of living animal tissue. Unlike previously developed experimental methods of light control, optogenetics allows researchers to use light to turn cells on or off with remarkable precision and resolution (down to individual cells or even regions of cells) in living, freely moving animals.
Genetically encoded tools enable activation and silencing of neurons with light, revealing how the brain works and facilitating potential new therapies.
Complexities of the human mind have been beyond the scope of understanding because a intricate neuronal network and difficulty in specific localization and assessment of area responsible for a specific behavior; more so in a freely moving living being. Optogenetics off late has been able to address this issue to great extent and holds promises for future. Relevant literatures in this direction were looked into and the salient aspects of this science is being discussed here with specific relevance to psychiatry.
The optogenetic method provides new opportunities to analyse neural networks. This can be achieved by growing cultured nerve cells on micro or Nano patterned substrates. Cells can be stimulated or silenced simply by a light-beam with up to now unknown spatial precision. Only for registration of the light evoked signals electrodes devices are necessary. Results from these experiments are expected to be used for theoretical work on neural nets.
Experiments on photoreceptor deficient mice have shown that light evokes potentials in the visual cortex after the transduction of the ON bipolar cells with ChR2 in the retina. This indicates that the retina of the animals regained photosensitivity, which is transmitted via the optic nerve to the brain. Trajectories of the movement of the animals in the dark and in the light show clearly an increased activity in the light as it is obtained for wild type animals. It is conceivable that such an approach might be possible for blind humans, suffering e.g. the dry or the wet maculardegeneration. However, in order to come to this point many biomedical, biophysical and technical hurdles have to be surmounted. This would be an alternative to the technology, which implants photosensitive chips in the human eye, which is far away from a satisfying treatment.
Cardiac electrophysiology, specifically dealing with the ability to manipulate membrane voltage by light with implications for cardiac pacing, cardioversion, cell communication, and arrhythmia research, in general. We discuss gene and cell delivery methods of inscribing light sensitivity in cardiac tissue, functionality of the light-sensitive ion channels within different types of cardiac cells, utility in probing electrical coupling between different cell types, approaches and design solutions to all-optical electrophysiology by the combination of optogenetic sensors and actuators, and specific challenges in moving towards in vivo cardiac optogenetics.