Essay Sannus Story

What components of the nervous system are involved in physical sensation? How does sensory impulse move throughout the body?

Over the years scientists have noted many complaints of a strange form of pain called phantom limb pain. This pain is strange because it is located in an appendage that no longer exists. By many of the amputees the pain is described as totally unbearable. Phantom limb pain has even driven some victims crazy. For the amputee population this is a very real problem that definitely needs to be solved.

The human sense of touch is known as the somatic or somatosensory system. The skin is the biggest and most complex organ in the somatosensory system.The somatosensory system permits the human body to experience pressure, texture, temperature, and pain, and to see the position and development of the body's muscles and joints.The receptor cells in the skin can be separated into three useful classifications: mechanoreceptors that sense pressure and surface, thermoreceptors that sense temperature, and nociceptors that sense pain. Thermoreceptors distinguish changes in temperature utilizing two sorts of receptor cells: warm and cold. Thus, thermoreceptors on the skin detects the temperature signal using two specific receptors cell: warm and cold.

The part of the peripheral nervous system that carries sensory information to the CNS is designated

a) The structures and the afferent division of the peripheral nervous system that are involved in

The phantom limb pain the woman is experiencing is described as a painful condition of the amputated limb after the stump has completely healed. It is a chronic pain that occurs in more than 80% of amputees especially those who suffered pain in the limb before the amputation. Theories suggest that phantom limb pain results from redevelopment or hyperactivity of cut peripheral nerves, scar tissue or neuroma formation in the cut peripheral nerves, spinal cord deafferentation, and alterations in the thalamus and cortex. More so, the CNS integration, which involves reorganization and plastic modifications of the somatosensory cortex, effects the receptors in perceiving the pain of the amputated limb despite of the limb itself being absent. In addition,

The clinical presentation of DPN vary markedly from one patient to another depending on the type of sensory fibers involved. About 50% of patients is symptomatic, commonly present with a burning

Phantom Limb Pain (PLP) is a serious condition that occurs when a person who has lost a part of their body though amputation, trauma (brachial plexus), or loss of nervous connections in an appendage, perceives that the limb is still there and experiences sensations coming from this area. It was first described in 1866 by S. Weir Mitchell, an American neurologist, through a short story published in Atlantic Monthly. While Mitchell may then have wondered if this was specific to wounded Civil War soldiers, it has since been established as quite common (1). Over 70% of amputees report phantom limb pain for years after amputation (2). Several theories have been proposed regarding PLP, although there is still much to be

The earliest hypothesis regarding the cause of phantom limbs and pain was that of neuromas. These were thought to be nodules comprised of remaining nerves located at the end of the stump. These neuromas presumably continued to generate impulses that traveled up the spinal cord to portions of the thalamus and somatosensory domains of the cortex. As a result, treatment involved cutting the nerves just above the neuroma in an attempt to interrupt signaling at each somatosensory level (5). This and other related theories were deemed unsatisfactory because of the fact the phantom pain always returned, indicating that there was a more complex reason.

Modern prosthetic limbs have become very advanced in the last decade. They now have the ability to grip objects, have running limbs, and many more wonderful things. Although these prosthetics are great, they are lacking some key extras that amputees would relish. What amputees really want is their sense of feeling back. They want to reach out with their prosthetic limb and be able to tell if the stove is on or off. They want to be able to press the gas of an automobile. This sense, that all non-amputees take for granted, would be a great place to start the improvement of the perfect prosthetic limb. To accomplish such a daunting task, engineers must figure out an alternative source that could interact with the amputees still intact nerve endings. This way they can use their still functioning nerves to communicate with their pseudo-nerve and have the ability to move their prosthesis around with complete control of it and its sense of touch. I believe this has not

The muscular system, in conjunction with the skeletal system, is responsible for movement of the body among other things (VanPutte, 270). The ability of the human body to move has been critical in the survival of the species over the years—for example; escaping from predators is only possible with skeletal muscle contraction. Hansen’s disease generally only affects the peripheral nerves of the extremities, not the locations of the larger muscle groups; however the smaller muscles of the hands and feet are vital for the well-being of individuals. For example, it would be quite difficult to feed oneself without the use of hands. Unfortunately, extreme cases of Hansen’s disease cause paralysis of the individual’s hands and feet. Paralysis occurs due to deadening of the peripheral nerves, both sensory and motor. As the afferent neurons lose the ability to receive and send stimuli, the nerve impulses (action potentials) are sent to the central nervous system less and less often. Even so, the action potentials that are transmitted to the CNS still are unlikely to stimulate the skeletal muscles for contraction. This is because the efferent peripheral neurons of the hands and feet are damaged as well. In effect, the sensory nerves of the extremities cannot receive much stimuli, and the motor neurons are also less able to start the action potentials in the skeletal muscle

Sacks discussed the ideas behind the phantom limb and how they affected many peoples live. The most interesting story was about a sailor that accidentally cut off his index finger. For forty years he thought he would poke himself in the eye whenever he moved his hand to his face. One day he lost the feeling in his entire hand including his phantom finger and his problem was cured (Sacks 66-67). Up to 70 percent of amputees confirmed that they still feel or still thought a missing limb was there. They often feel that they can reach out and grab something. Some won't sleep in a certain way because they feel the missing limb between them and the mattress. The sensations felt stem from the activity of the sensory axons

The peripheral nervous system (PNS) is connected directly to the central nervous system, and consists of neurons and nerves that send information back and forth the CNS. Furthermore, the peripheral nervous system can be divided into two sections, the sensory nervous system and the motor nervous system. The Sensory The sensory nervous system is in charge of transmitting data from a variety of internal organs or from external stimuli to the central nervous system using sensory nervous cells. On the other hand, the cells of the motor nervous system (motor neurons), take the impulse from the CNS to effectors, which include glands and muscles. In addition, the motor nervous system can be further divided into the somatic nervous system, controls voluntary actions of the skeletal muscle and external sensory organs, whilst the autonomic nervous system operates

Leprosy predominantly affects the skin and the nerves outside the brain and spinal cord, called the peripheral nerves. The peripheral nerves are the portion of the nervous system that is outside the brain and spinal cord. The main function of the peripheral nerves is to connect the central nervous system to the limbs and organs, essentially serving as a relay between the brain and spinal cord and the rest of the body. Other major symptoms of leprosy

Phantom limb pain is a painful sensation experienced in a body part which is no longer part of the body, often due to amputation.(3) Individuals also reported that tingling as well as various types of pain have occurred, and these sensations may eventually disappear or may persist as cramping, shooting, burning or crushing