Reflexes are involuntary movements which are caused as part of a reaction to a stimulus. [Purves (2004). Neuroscience: Third Edition. Massachusetts, Sinauer Associates, Inc.] In the practical, three experiments were carried out in which reflexes were stimulated and measured. Each of these experiments were based on the process of a monosynaptic stretch reflex. The monosynaptic stretch reflex sends signals to be processed in the spinal cord, as opposed to the signal travelling to the brain, as with other sensory inputs leading to motor outputs. When the reflex is being activated, sensory neurons synapse with motor neurons in the spinal cord without the use of interneurons between them. This passage of information usually takes 1-2 milliseconds. Both mechanical and electrical stimulation of the stretch reflex can occur, the electrical due to the muscle spindle being able to act as a receptor. An example of both a mechanically stimulated stretch reflex, the Myotatic reflex, and electronically stimulated stretch reflex, Hoffman’s reflex, was demonstrated in the practical. [ prac manual]
The Myotatic reflex, or the patellar reflex, is the most common reflex. It is a reflex which causes the lower leg to kick forward slightly and is
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The Jendrassik manoeuvre is carried out by a subject clasping their hands together, as two hook shapes, interconnected and pulling them apart as strongly as they can when the tendon is being stretched by use of the hammer hitting the tendon below the knee in the patellar reflex. This helps stimulate the patellar reflex. In comparison to the patellar reflex without the use of the Jendrassik manoeuvre, the magnitude of response by the reflex will be bigger. The subject may be unconsciously preventing or the reflex from and the Jendrassik manoeuvre will take the subject’s mind off the effect of the reflex. ***
In the beginning phases of muscle contraction, a “cocked” motor neuron in the spinal cord is activated to form a neuromuscular junction with each muscle fiber when it begins branching out to each cell. An action potential is passed down the nerve, releasing calcium, which simultaneously stimulates the release of acetylcholine onto the sarcolemma. As long as calcium and ATP are present, the contraction will continue. Acetylcholine then initiates the resting potential’s change under the motor end plate, stimulates the action potential, and passes along both directions on the surface of the muscle fiber. Sodium ions rush into the cell through the open channels to depolarize the sarcolemma. The depolarization spreads. The potassium channels open while the sodium channels close off, which repolarizes the entire cell. The action potential is dispersed throughout the cell through the transverse tubule, causing the sarcoplasmic reticulum to release
In order for a body to move, a muscle has to be activated by an electrical impulse. The electrical impulse sends a message to the parietal lobe, frontal lobe, and cerebellum. The message then works its way through the spinal cord next to nerve pathways to the muscles which activate movement. Kinesthetic arts to stimulate motor activity. Motor activity is followed by swift thought processes that set goals, predict outcomes, analyze variables and complete movements.
This report will explore the structure and function of skeletal muscle within the human body. There are three muscle classifications: smooth (looks smooth), cardiac (looks striated) and skeletal (looks striated). Smooth muscle is found within blood vessels, the gut and the intestines; it assists the movement of substances by contracting and relaxing, this is an involuntary effort. The heart is composed of cardiac muscle, which contracts rhythmically nonstop for the entire duration of a person’s life and again is an involuntary movement of the body. The main focus of this report is on skeletal muscle and the movement produced which is inflicted by conscious thought unless there is a potentially harmful stimulus and then reaction is due to reflex, as the body naturally wants to protect itself. Skeletal muscle is found attached to bones and when they contract and relax they produce movement, there is a specific process that the muscle fibers go through to allow this to occur.
In conclusion, this brief review suggests that the literature is contradictory in the theory that muscle fibres during a CMJ are less beyond optimum length in comparison to SJ, in turn allowing an increased force during the initial part of their shortening, causing the storage of elastic energy that can then be reutilized during the propulsion phase, therefore further research is necessary. However, it does seem that from a biomechanical perspective the active state development during the preparatory countermovement in a CMJ may increase force by the hip extensors and more work during shortening in CMJ and therefore a greater vertical force and jump height.
This is when pressure is applied to the hands or feet by a thumb technique with no lotion. There are different points on the feet are related to different parts of the body. It has been shown that reflexology helps with pain and stiffness in Rheumatoid Arthritis sufferers. The patients also claim that due to reflexology they have used less painkillers and generally feel healthier.
This is important for feeding. The rooting reflex is a reflex that occurs when the babies mouth is stroked. The baby will turn around look for the nipple and begin to make sucking motions. The grasping reflex occurs when something is placed in the infants hand or thier palm is stroked the infants hand closes. At this age their grip is very strong. When the sole of their feet is placed on a surface they will attempt to walk even though they might not be able to support their own weight yet this is the stepping reflex. The startle reflex is an involuntary movement of the babies body, arms and legs when it is startled by a loud noise or sudden
Reflexes are automatic responses that children cannot control. They are innate and automatic. A few of the reflexes infants have are:
John McDowell’s concept of ‘second nature’ has been considered to be the most controversial and debatable element in his philosophy of mind. Discuss McDowell’s concept of ‘second nature’ and compare it a specific monist theory of mind which another philosopher has proposed.
Any activity, conscious or unconscious, of our body that involves movement, strength or uniform control of a position depends on the action of the muscular system, controlled by the brain and spinal cord through a complex network of neural circuits continuously leading the commanding signals.
[3] H. S. Milner-Brown, R. B. Stein, and R. Yemm. "The Orderly Recruitment of Human Motor Units during Voluntary Isometric Contractions." The Physiological Society 230th ser. (1973): 359-70. Web. 22 May 2014.
The Squat is a natural movement humans have done since they existed. If you pay attention you’ll notice people all over the world Squat, often unconsciously. Quick examples… Babies routinely play while sitting in a Squat position, and will Squat to stand up. Asian people often
The dictionary definition of Empathy is the psychological identification with or vicarious experiencing the feelings, thoughts, and attitudes of others. Simply put, empathy is the ability to step into someone else’s shoes, be aware of their feelings and understand their needs. In the workplace, empathy can show a deep respect for co-workers and show that you care, as opposed to just going by rules and regulations. An empathic leadership style can make everyone feel like a team and increase productivity, morale and loyalty. Empathy is a powerful tool in the leadership belt of a well-liked and respected executive (Pressley, 2012).
Throughout the ages, humans have had an inherent interest in studying the complex area of human behaviour, even before psychology was established as a science. Because the study of behaviour is so broad and multifaceted, its scientific study poses particular challenges. Therefore, it can be beneficial to approach the scientific study of human behaviour from the perspective of cognitive psychology. This is the study of cognition, the mental processes that underlie human behaviour (Ling & Cattling, 2012).
This reaction is a reflex - it was not a direct command. However, if a person’s reflex pathway was or is disrupted in some way, he or she might not be able to transmit the information to his or her brain fast enough to avoid getting burned, or they might not even be able to sense the heat until it is too late. Also, there are several reflex reactions that respond to instability, such as the knee jerk. The knee jerk is a sudden kicking movement made when something or someone roughly taps on the patellar tendon, which is located right below the kneecap. The tap causes a slight stretch in the quadriceps, which is the front of the upper leg. This causes the muscles to contract in reaction, and therefore straighten the leg through a kicking motion. Absence of the reaction indicates that the central nervous system may be damaged. Doctors also use the knee jerk reflex to help in recognizing thyroid disease. The knee jerk, also known as the patellar reflex, is one of the many forms of a spinal reflex. A spinal reflex is sought to be important due to its automatic responses to stimuli that require no thinking activity and is a form of protecting
Have you ever wondered why people have certain reactions? I chose chapter eight on emotions for my reflection paper because emotions are something that everyone has and feels, yet cannot always explain or react to in the way you would expect. Personally, I have never been great at responding to emotions in a way that I would not regret in the future. Thus, naturally being drawn to this chapter as a way to expand my knowledge on how to react to things more positively. I also wanted to learn why I feel a certain way after events that would not affect most people and be reassured about my feelings. Opposite to that, it is nice to see that, while not always productive, others have the same reaction habits. Overall, emotions are a complicated