Optogenetic Activation and/or Inhibition of Neurons

The progress of neuroscience has been significant in the past 500 years. and with the advance of technology, there is yet a multitude of chapters left to write in the history books of neuroscience. The book The Tale of the Dueling Neurosurgeons: written by Sam Kean was an engrossing and captivating read. It gives the reader a better appreciation for the growing pains of neuroscience and provides an educational, albeit entertaining overview of the anatomy and physiology of the brain and nervous system. From the early life and discoveries of Santiago Ramón y Cajal and his fascination with Golgi’s method la razione nera, which allowed Cajal to deduct after observing

In the Summer of 2015 I had the opportunity of accomplishing my own research project. With the help of my graduate student, I led us to better understand the neural pathway

As an action potential travels down the axon of the presynaptic neuron, the action potential reaches the axon terminal synaptic vesicles which migrate toward the synapse. They then release neurotransmitters into the synaptic cleft. The neurotransmitters travel through the synaptic cleft and bind to ligand-gated ion channels on the postsynaptic neuron membrane. The channels open and allow chemicals to enter the cell (i.e. sodium). Then positively charged sodium enters the cell and causes the cell to depolarize. The depolarization spreads down the axon and an action potential is generated. The process then starts over at the axon terminals.

DISCUSSION: Rat #4 demonstrated similar responses during light on and light off periods. However, it learned to press more during light on periods, as it pressed 109 times when the light was on, and only 92 times when the light was

According to current research there are about 800,000 ganglion cells in the human optic nerve (J.R. Anderson, 2009,pg. 35). The ganglion cells are where the first encoding of the visual information happens. Encoding is the process of recognizing the information and changing it into something one’s brains can understand and store. Each ganglion cell is dedicated to encoding information from a specific part of the retina. The optic nerve goes then to the visual cortex and the information enters the brain cells. There are two types of cells that are subcortical, or below the cortex; the lateral geniculate nucleus and the superior colliculus. The lateral geniculate nucleus is responsible for understanding details and recognizing objects. The superior colliculus is responsible for understanding where objects are located spatially. This collection of cells working together is called the “what-where” distinction. The division of labor continues, as the information is further processes. The “what” information travels to the temporal cortex, the “where” information travels to the parietal regions of the brain.

This experiment’s results and mechanisms relates current medical disease which well known as autism spectrum disorder (ASD). Symptoms of ASD are difficulty of communication and interaction with others and inadequate eye contact. When GRIP proteins do not interact with AMPAR receptor, ASD were developed due to genetic mutation of the GRIP. GRIPs are located on the presynaptic and postsynaptic cell, but when diagnosing ASD disease, only postsynaptic cell were observed to detect ASD. The reason I am desiring to predict activity in presynaptic cell is to understand neuron activity. Knowing that allows to regulate protein and receptor and manipulate the neurons the way genetics want to cure ASD. If geneticist know how neurons

The development of the human body is an exquisite process that involves numerous complicated processes for even the smallest of body parts, including the eyes. The eyes are an extraordinarily complex organ capable of gathering information through refracted light and sending it the brain to assemble a picture. They provide the ability to see and follow a moving object and the capability to tell an approximate distance of an object. When light passes through the cornea and iris pupil, at the anterior portion of the eye, it is focused by the lens onto the retina at the back of the eye. Photoreceptor cells, which are present in the retina, detect the light and send information to interneurons which begin to sort out the information. This information is then sent to ganglion cells which transmits the final information to the brain (Sowden 199). Because the eyes have such complicated and exquisite processes, the likelihood of developmental errors occurring are possible. A large number of these developmental errors lead to congenital defects and abnormalities that effect the individual’s eye sight. Some of these defects and abnormalities can cause serious diseases and syndromes that effect more than just the eyes, but also neurological processes, facial dimorphisms, growth failure, tracheal development, and genitalia anomalies.

The brain is a unique organ, it allows us as humans, for example to imagine, speak and perform a lot more complex functions. To function well as a complex organ, the brain has a lot of cells. The brain consists of neurones and glia cells. Neurones observe changes from the environment, communicate these changes to other neurones and issue commands to the body to react on these changes. Glia cells give the neurones among other things protection and support. Neurones are really small cells composed of two parts: the soma, which contain the cell nucleus and neurites, which are projections from the soma. There are two different types of neurites, the axon and the dendrite. Dendrites receive signals to transfer to the neurones and axons carry the output of the neurones. Figure 1 gives a schematic overview of a neuron and shows the dendrites, cell body and axon. This essay will discuss the structure of neurones and the different types of neurones further in detail. It will start with the structure of a typical structure of a neuron and then the different types of neurones, the sensory-, motor- and interneurones. (Bear, M.F. et al. (2007))

I have elected to pursue research in the field of neuroscience because I relish the approach of logical thinking to satisfy the curiosity of knowing things about me and the world around me. Neuroscience is a fascinating area with a limitless possibility of understanding and uncovering to resolve so many unanswered and unimagined questions. Although, in recent years, a large number of breakthroughs research have been done in the area of neuroscience, still, there is a lot more to discover and untangle in this area. Such an enormous amount of research work in this area has led open to the advancement in the diagnosis and therapeutic approaches to several neurological disorders and cancer such as glioma. Therefore, I decided

Have you ever thought about how a scientist knows how to deal with certain brain problems? Neuroscientists are using new and unique research methods to achieve a number of benefits. In this paper I will be explaining why this claim is true. My first main point will be how by using magic it can help with brain problems. The second main point will be, by studying the brain scientists can learn how to treat brain problems.

Research during the last three decades has led to the advancement of retinal implants. The aim is to replace functioning of lost/damaged retinal cells, by stimulating cells electrically. The studies surrounding this breakthrough are still being conducted and enhanced upon. Retinal implants are not perfect and the more research that is done to further the understanding of how to manipulate the technology, the implants will become more successful in restoring

Within the human anatomy, an intricate and complex network of specialised nerve fibres and neurons works in collaboration with the central nervous system and peripheral system, designed to carry out the various actions humans perform every day. The nervous system is also known as the master control unit of the human body, as it operates other major functions such as the circulatory and respiratory systems (Jakab, 2006). It is composed of the central nervous system (CNS) and the peripheral nervous system (PNS). The neurons established within the various sections of the nervous system, is structured with three main parts: a dendrite which is a cluster of branches that operates by receiving information from the

Axons are sensitive and their respond depend on the local environment. When the tectum is removed, retinal axons grow toward the missing tissue, demonstrating that optic axons utilize these neighbourhood signals as opposed to a long-run diffusible attractant from the tectum as they grow along the optic tract (Taylor, 1990). In the event of a small piece of the optic tract neuroepithelium is turned 90° preceding the axons enter it, then they become misoriented when they enter the pivoted transplant (Harris, 1989) and correct their course of growth once they exit. These results confirm that the neuroepithelium contains local information to which growing axons respond and that they are not simply following gradients of attractants released by their targets (Sanes et al., 2012). Growth cone filopodia are long, motile, and covered with receptors, also have a very high surface to volume ratio, which can help convert membrane signals into large changes in intracellular messengers such as calcium. Filopodia can show localized transient elevations of intracellular calcium and these transients reduce filopodial motility (Sanes et al., 2012). Calcium transients can be directly artificially activated in growth cone filopodia by loading neurons with a calcium caging agent that releases calcium upon stimulation with a pulse of light (Gomez et al., 2001). Experiments in which calcium is uncaged on one side of a growth cone generally cause the growth cone to turn toward the side that has

The most promising at the moment is optogenetic defibrillation. Optogenetics is the combined use of genetic and optical techniques for functional sensing and control in biological tissue [41]. Using genetically introduced light-gated ion channels and pumps, optogenetics offers alternatives to traditional method of excitation and suppression. In particular, Channelrodopsin-2 (ChR2), a light sensitive protein, and its variants have widespread application as optical actuators in neuroscience and now are being used in experimental cardiac research.

The neurons in the brain tissue communicate with each other via electrical signals, generating measurable action potential activity. Electrophysiological techniques have been developed to measure this electrical activity. Electrophysiological techniques are some of the classic methods of brain research, partly because they are very sensitive and accurate. They provide quite a number of insights into the subject’s mind as well as allow for study of how the brain works. They can be used during brain surgery as well as when the patient is awake and conscious, as the brain itself does not sense pain during the measurements. Although electrophysiology has been around for close to half a century, it has attained appreciable advances only in the last two decades. These advances have revolutionized the study of brain structure and functions, allowing neurophysiologists to monitor the brain’s activities directly during experiments (Sutler et al., 1999). Even with its significant impact in neurology, however, its presence has been so commonplace that many people no longer realize its ubiquity. This essay explores three electrophysiological techniques namely patch clamp, sharp electrodes, and brain slice recording. It describes how each of these techniques works as well as how advances in the techniques have