The skin contains numerous sensory receptors which receive information from the outside environment. The sensory receptors of the skin are concerned with at least five different senses: pain, heat, cold, touch, and pressure. The five are usually grouped together as the single sense of touch in the classification of the five senses of the whole human body. The sensory receptors vary greatly in terms of structure. For example, while pain receptors are simply unmyelinated terminal branches of neurons, touch receptors form neuronal fiber nets around the base of hairs and deep pressure receptors consist of nerve endings encapsulated by specialized connective tissues. Receptors also vary in terms of abundance relative to each other. For example, there are far more pain receptors than cold receptors in the body. Finally, receptors vary in terms of the concentration of their distribution over the surface of the body, the fingertips having far more touch receptors than the skin of the back.
Other types of receptors located throughout the whole body, including proprioceptive receptors and visceral receptors, receive information about the body's internal environment. Proprioceptive or stretch receptors, located in muscles and tendons, sense changes in the length and tension of muscles and tendons and help to inform the central nervous system of the position and movement of the various parts of the body. Each stretch receptor consists of specialized muscle fibers and the terminal branches of sensor neurons. The muscle fibers and sensor neuron endings are very closely associated and are encased in a sheath of connective tissue.
Visceral receptors monitor the conditions of the internal organs. Most responses to their stimulation by an organ are carried out by the autonomic system. Several visceral sensors, however, produce conscious sensations such as nausea, thirst, and hunger.
Touch Receptors are the nerves cells that tell your brain about tactile sensations. There are several types of touch receptors, but they can be divided into two groups. Mechanoreceptors that give the sensations of pushing, pulling or movement, and thermoreceptors that tell you about sensations of temperature.
The mechanoreceptors contain the most types of touch receptors. Free nerve endings inform the brain about pain, and they are located over the entire body. Located in the deep layers of dermis in both hairy and glabrous skin, the pacinian corpuscles detect pressure, telling the brain when a limb has moved. After the brain has told a limb, such as an arm, to move, the pacinian corpuscles tells the brain that that limb has actually moved into the correct position.
Each sensation has its own neuronal receptor, such as: “mechanosensation, thermosensation, vibration, joint position, chemosensation, and electrosensation.” Oaklander then discusses “nocifensive sensations,” or senses that defend us from danger, such as pain and itch. These sensations trigger reflexes and strong movements. However, something that is often left undetected is chronic neuropathic pain, which can cause nerve damage. Shingles is a result of chronic neuropathic pain.
The integumentary system is composed of the skin and the structures related to the skin, which include the hair, the finger nails, the sensory receptors and the glands (Shier, Butler, & Lewis, 2009). This system has an important function since it provides protection to the body, helps to maintain body temperature, and contains sensory receptors (p.117). The skin has essential function such as regulating homeostasis and body temperature, also delaying the loss of water from deeper tissues, storing sensory receptor, synthesizing biomechanical, and discharging waste from the body (p.117). The skin has two layers: the epidermis (outer layer) and the dermis (inner layer) (p.117). There is also a subcutaneous layer or hypodermis (p.117). According to Shier, Butler, and Lewis 2009 “as its name indicates, this layer is beneath the skin and not a true layer of the skin” (p.117). This layer has the blood vessels that supply the skin (p.117).
This paper aims to endorse physicalism over dualism by means of Smart’s concept of identity theory. Smart’s article Sensations and the Brain provides a strong argument for identity theory and accounts for many of it primary objections. Here I plan to first discuss the main arguments for physicalism over dualism, then more specific arguments for identity theory, and finish with further criticisms of identity theory.
Touch is as essential to a healthy and happy life as eating right, getting proper sleep, and exercising. With the world growing more technological, the need for healthy human contact is more important than ever. Massage and body therapies are an age old healing refuge for us in this fast-paced, stressed-out world. The practice of massage therapy is rapidly growing in the United States. It has so much to offer and is becoming more widely accepted by doctors and the general public. Massage is touching another person by such movements as rubbing, kneading, pressing, rolling, slapping, and tapping. This type of therapy provides circulation of the blood and lymph, relaxation of muscles, relief from pain, restoration of metabolic balance, and many other benefits both physical and mental. There is much historical evidence to indicate that massage is one of the earliest remedies for pain relief and for the restoration of a healthy body. It is said to be the most natural and instinctive means of relieving pain and discomfort. Massage has proven to be an effective method for treating many conditions for thousands of years and it will continue to be used for thousands of years to come. Massage therapy is a great treatment for the body and soul.
Sensory neurons behave to physical stimuli such as light, sound and touch and send observation to the central nervous system about the body’s surrounding environment. Motor neurons, based in the central nervous system or in peripheral ganglia, disseminate signals to mobilize the muscles or glands.
Touch---travels through spinal cord---into medulla---left side functions of the body is controlled by the right side of the brain and the right side of the body is controlled by the left side of the brain.
In this lab we apply the technique known as a two point discrimination test. This test will allow us to determine which regions of the skin are best able to discriminate between two simultaneous sensory impulses. According to (Haggard et al. 2007), tactile discrimination depends on the size of the receptive fields located on the somatosensory neurons. However receptive fields for other types of sensations are located elsewhere. For vision we find that the receptive fields are located inside the visual cortex, and for hearing we find receptive fields in the auditory cortex. The ability for the body to discriminate two points depends on how well that area of the body is innervated with neurons; and thus conferring to the size of the receptive fields (Haggard et al. 2007). It is important to note that the size of the receptive field generally decreases in correlation to higher innervations. As was seen in the retinal receptive fields, the peripheries of tissue had contained larger receptive fields (Hartline, 1940). In our test we hypothesized that the finger region will be able to discriminate better than the forearm. This means that they will be much more innervated with neurons than the forearm, and likewise contain smaller receptive fields. This also means that convergence is closer to a 1:1 ratio, and is less the case the farther from the fingers we go. We also think that the amount of convergence is varied with each individual. We will test to see if two people will have different interpretations of these results.
In each zone, impulses and reflexes travel until they reach nerve endings in the feet and the hands. These zones are believed to be meridians along which energy flows. Placing pressure on the nerve endings in the hands and the feet will affect the organs found in that particular zone (http://www.reflexology.org/aor/refinfo/healart.htm). As well as longitudinal zones throughout the body, there are also cross-reflex points. These cross-reflex points are corresponding points on the opposite side of the body which can be useful in administering reflexology treatment when pressure is not able to be placed on the reflex point....
The Nervous System can be divided into two different categories, the central nervous system (CNS), and the peripheral nervous system (PNS). The CNS is made up of the brain and spinal cord, and the PNS is made up of the rest of the nerves that connect the brain and spinal cord to the rest of the body. The major functions of the nervous system are sensory, integrative and motor function. The sensory function of the nervous system receives sensory receptors by detecting changes inside and outside of the body. The integrative function processes the information. Motor nerves convey information from the CNS to the body, and make the necessary response (Herlihy & Macbius, 2000).
Sensation refers to the process of sensing what is around us in our environment by using our five senses, which are touching, smell, taste, sound and sight. Sensation occurs when one or more of the various sense organs received a stimulus. By receiving the stimulus, it will cause a mental or physical response. It starts in the sensory receptor, which are specialized cells that convert the stimulus to an electric impulse which makes it ready for the brain to use this information and this is the passive process. After this process, the perception comes into play of the active process. Perception is the process that selects the information, organize it and interpret that information.
Visual perception and visual sensation are both interactive processes, although there is a significant difference between the two processes. Sensation is defined as the stimulation of sense organs Visual sensation is a physiological process which means that it is the same for everyone. We absorb energy such as electro magnetic energy (light) or sound waves by sensory organs such as eyes. This energy is then transduced into electro chemical energy by the cones and rods (receptor cells) in the retina. There are four main stages of sensation. Sensation involves detection of stimuli incoming from the surrounding world, registering of the stimulus by the receptor cells, transduction or changing of the stimulus energy to an electric nerve impulse, and then finally the transmission of that electrical impulse into the brain. Our brain then perceives what the information is. Hence perception is defined as the selection, organisation and interpretation of that sensory input.
First, one must have the five senses; taste, smell, hear, see, and feel. Yes, these are physical aspects, however, these senses are what any human needs to be, human. For example, the human body needs to be able to taste. It must ingest food, and the food must appeal to a decent taste. A human must also be able to smell, so one may smell a poisonous gas, delicious food, or any other stench that may linger in the air. To be able to hear, enables the human to hear danger or a noise that appeals to them. When seeing, danger is also noted as well as the care of others. When one feels, the object that is being felt may make the person feel comfortable. Not only the sense of touching, but feelings.
Vision is one of the key sensory systems that primates rely on to achieve remarkable success throughout life. Vision, as depicted by the authors of dictionary.com refers to sensing with eyes (dictionary.com, 2017). The sensory system vision, has several key components and receptor cells involved in order for the eye to communicate information to the brain and through the rest of the body. Throughout this paper, a clear and precise explanation of what those key components are will be discussed, as well as how the brain interacts with the images portrayed by the eye.
The five senses of sight, hearing, touch, taste and smell are all sensations throughout the human body. Sensation is the involvement of sensory receptors as well as the central nervous system in order to allow us to experience outside stimuli. The system that allows us to experience sensation is the sensory system.
The human nervous system is composed of many different parts and performs many different functions. It is said to be the “body’s electrical wiring.” (Zimmerman) The nervous system itself is capable of collecting information, processing it, and then responding to the collected information where it then sends it to the appropriate part of the body to perform bodily functions. (Miller and Levine) The nervous system, as hinted in the name, is composed of many different nerves which are cylindrical bundles of fibers. These nerves start at the brain and proceed to branch down throughout the body. (Zimmerman) The human nervous system is made up of two main zones; The Central Nervous System and The Peripheral Nervous System. These two main categories are interdependent and work together to maintain homeostasis internally and externally. (Kinser)