A description of the nervous system

Cell Body of a Neuron The cell body is like any other cell with a nucleus or control center. Dendrites The cell body has several highly branched, thick extensions that appear like cables and are called dendrites.

A description of the nervous system

The Neuroscience on the Web Series: General Description of the Central Nervous System The Cortex The two hemispheres of the brain are covered by a layer of cells called the cortex. Cortex means "bark" in Latin. The surface of the cortex is ridged, as it is made up of gyri and sulci. A gyrus is a raised fold of tissue.

A sulcus is a groove between two gyri. A particularly deep sulcus is called a fissure as in the fissure of Rolando or the central sulcus which separates the frontal and parietal lobes. So sometimes the labels can be interchangeable.

A convolution includes both a gyrus and sulcus. Because it is convoluted, a large amount of cortical tissue fits into a relatively small area. The Subcortical Structures The Basal Ganglia The basal ganglia or basal nuclei is made up of two structures, the caudate nucleus and the lenticular nucleus.

The caudate nucleus is bounded on one side by the lateral ventricle and is divided into a head, body and tail. The lenticular nucleus is a lens-shaped structures that has two components: The putamen is the more lateral of the two. The basal ganglia is a very important part of the extrapyramidal tract.

It is the basal ganglia that is responsible for a natural and spontaneous smile, which is quite different from the phony smiles we see in photographs, which originate in the cortex and are transmitted on the pyramidal tract which is responsible for volitional movement.

The Internal Capsule The internal capsule lies between the lenticular and caudate nuclei. It is a group of myelinated therefore white afferent and descending fiber tracts including the pyramidal tract that connects the cortex to other parts of the central nervous system.

The pyramidal tract begins as a corona radiata radiating crown from motor cells in the premotor, primary motor where most of the motor cells originateand primary sensory areas of the cortex and converges into the internal capsule.

The capsule itself ends within the cerebrum, but the axons that pass through it continue down to the brain stem, and spinal cord. Because so many axons join together to pass through this area, the internal capsule is sometimes referred to as a bottleneck of fibers.

Despite its close proximity to the caudate nucleus and lenticular nucleus, the internal capsule is not part of the basal ganglia. The internal capsule and the basal ganglia are collectively referred to as the corpus striatum. The Limbic System This is the most ancient and primitive part of the brain.

It is sometimes called the rhinencephalon as the term "rhino" means nose in Latin and some of this area is dedicated to the processing of olfactory stimuli.

A description of the nervous system

The limbic system is involved, among other things, with emotion and memory, particularly new memories. The Thalamus This subcortical structure sits within the brain at the level of the temporal lobe.

It is well protected in this location. The thalamus is made up of three parts, including two thalamic bodies and the tissue that connects them which is called the massa intermedia, or the interthalamic adhesion.

The thalamic bodies are separated by the third ventricle, one of the spaces in the brain that is filled with cerebral spinal fluid. The massa intermedia lies within the third ventricle.

Nervous System Physiology

The thalamus receives and organizes sensory information from the periphery. Messages from all sensory modalities with the exception of smell pass through the thalamus on their way to cortical centers and other structures for further processing.

Information about smell travels directly to the temporal lobe. Sensory information, including touch and kinesthesia passes from the thalamus to the parietal lobe. Auditory information comes into the thalamus from the inferior colliculi of the midbrain. It is processed by the medial geniculate bodies of the thalamus before being sent to the temporal lobe.

From there it is sent to association areas for further processing. Visual information comes into the thalamus from the superior colliculi of the midbrain.The nervous system is a complex network of nerves and cells that carry messages to and from the brain and spinal cord to various parts of the body.

The nervous system includes both the Central nervous system and Peripheral nervous system. The two hemispheres of the brain are covered by a layer of cells called the cortex.

A description of the nervous system

(Cortex means "bark" in Latin.) The surface of the cortex is ridged, as it is made up of gyri and sulci. A gyrus is a raised fold of tissue.

A sulcus is a groove between two gyri. A particularly deep sulcus is called. The nervous system of vertebrates (including humans) is divided into the central nervous system (CNS) and the peripheral nervous system (PNS)..

The (CNS) is the major division, and consists of the brain and the spinal cord. The spinal canal contains the spinal cord, while the cranial cavity contains the brain. The CNS is enclosed and protected by the meninges, a three-layered system of. The nervous system is a complex collection of nerves and specialized cells known as neurons that transmit signals between different parts of the body.

It is essentially the body's electrical wiring. Structurally, the nervous system has two components: the central nervous system and the peripheral nervous system. The two hemispheres of the brain are covered by a layer of cells called the cortex.

(Cortex means "bark" in Latin.) The surface of the cortex is ridged, as it is made up of gyri and sulci. A gyrus is a raised fold of tissue. A sulcus is a groove between two gyri. A particularly deep sulcus is called.

nervous system the organ system that, along with the endocrine system, correlates the adjustments and reactions of an organism to internal and environmental leslutinsduphoenix.com is composed of the brain, spinal cord, and nerves, which act together to serve as the communicating and coordinating system of the body, carrying information to the brain .

Nervous system - Wikipedia