Dendritic Spines Analysis : Utilizing Light Microscopy

4.On a neuron, the branch-like structures that receive messages from other neurons are the dendrites.

According to Carlson (YEAR), neuron (nerve cell) is defined as,” the information-processing and information-transmitting element of the nervous system”. The shape and variety will depend on the specialized job they perform. The majority of neurons have in common in one form or another, the four structures or regions: the cell body or soma, axon, dendrites; and terminal buttons. The soma or the cell body contains the nucleus which regulates all cell activity. Dendrites is derived from the Greek work Dendron, for tree, because they resemble trees. The dendrite is attached to the cell body of the neuron which receives information and

Dzevdet Smajlovic, professor from the Department of Neurology at the University of Tuzla in Bosnia stated that

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

Describe the anatomy of the neuron and the ways that neurons communicate with each other.

2.Dendrite are the receptive region of the neuron. They conduct electrical impulses toward the cell body.

First and foremost, dendrites are truly interesting cells within the host body. A neuron is a tiny, microscopic cell. Often, neurons are confused with nerves, but both are different things. Neurons are not nerves, although both are related! Nerves are made from a large bundle of axons and dendrites and are macroscopic or visible to the naked eye (Chabner 346; Coon and Mitterer

There are many type of neurons. They vary in size from 4 microns (.004 mm) to 100 microns (.1 mm) in diameter. Their length varies from a fraction of an inch to several feet.

VII) Describe how the shape of the thalamus and brainstem reflect the presence of impinging cortical structures along the antero-posterior axis. Describe the difference between sheep and human brains.

The primate visual system is usually separated in two partially independent pathways; the dorsal pathway subserves mostly motion perception, while the ventral one subserves object feature recognition. The primary visual cortex (V1) receives most of its retinal input through the lateral geniculate nucleus (LGN). Anatomical and functional segregation of visual perception starts at the level of the retina, where parvocellular (P) ganglion cells have small receptive fields and have sustained colour-sensitive synaptic response to light, whereas magnocellular (M) ganglion cells have larger receptive fields and a faster adapting achromatic response to light [Livingston et al., 1992]. Both types of cells project to the layers 3-6 and 1-2 of the LGN, respectively, which in turn send most of their outputs to layers 4Cβ and 4Cα of V1, forming what is known as the P and M pathways [Refs].

Fig. __ Feed-forward projections from the eyes to the brain and topographic mapping. In each eye the visual field on the left and right of the fovea (the cut goes right through the fovea!) projects to different cortical hemispheres: the ipsilateral retina projects to the ipsilateral visual cortex, and the contralateral retina crosses the contralateral cortex (hemifield crossing in the optic chiasma). The first synapse of the retinal ganglion cells is in the lateral geniculate nucleus (LGN), but information from the left (L) and right (R) eye remains strictly separated. The LGN consists of six layers, layers 1 and 2 are primarily occupied by the magnocellular pathway, and 3–6 by the parvocellular. Information from both eyes comes first together

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.

Neurons have a part called the dendrites and this is where the neuron fires a correct impulse to another neuron through the axon. Axon is a long projection that connects nerve cells.

___________ is a stain used in brain image analysis that can illustrate the number of neurons.

To visualize the sections and eventually the SNB neurons we used the computer where the photos were regrouped in a folder. The goal was to count the number of SNB motorneurons in each section and recorded in a chart. Then, we summed up the number of neurons per rat; and times it