18) Consists of an ipsilateral withdrawal reflex and a contralateral extensor reflex; important in maintaining balance.…
The sensory receptor detects a stimulus. The interneurons receive inputs from sensory receptors and synapse on motor neurons. The effects on motor neurons can be excitatory or inhibitory. Lastly, motor neurons produce muscle contraction, and motor response. Reflexes often have effects in groups of motor neurons to different muscles; sometimes at different joints in the same limb or in a different limb. Reflexes are valuable tools for clinical evaluation of how our nervous system is functioning. For reflex to occur, all elements must be functional and our pathways must be intact. If reflexes are absent, the physician can diagnose where the pathway has been interrupted and can diagnose where function is compromised.…
1. Amy has numbness of her pinky, ring finger, and medial surface of her right arm. After neurological testing, it is determined that she has a compressed spinal nerve on the right side.…
Sensory and motor neurons carry signals to and from the spinal cord and brain, while the interneurons in the spinal cord and brain process received signals and send out new signals for the appropriate bodily response.…
Define the terms reflex and spinal reflex and identify the components of a reflex arc.…
A good example of a reflex is the “knee-jerk” response the doctor tests during a physical examination. In a healthy person, this stretch reflex maintains posture and allows our muscles to hold up our body. Doctors can check this reflex by tapping on the tendon just below the kneecap. This tap causes contraction of the quadriceps muscle and extension of the leg. Stretching of the muscle activates nerve impulses which travel to the spinal cord. Here the incoming impulses activate motor neurons, which travel back to the muscle and result in muscle contraction.…
Spinal muscular atrophy [SMA] is a disorder in which, you have a loss of motor neurons. Your muscle symmetry is often off. In addition, there is muscle weakness in your spinal cord. This occurs in a hard time sitting up and holding your head up on your own. It is just like when you are a newborn and you need a pillow to sit on the couch. A few major causes of SMA are loss of motor neuron cells or nerve cell. This mutation leads to a deficiency of motor neuron cells or nerve cells. The disorder SMA is tied to the gene "SMN1" and tied to chromosome 5. A few symptoms of this disorder are- difficulty breathing lack of oxygen, difficulty eating, floppy posture, small amount of movement, and all these symptoms will gradually get worse over time. All these symptoms are at about a mild level in the beginning.…
response. Electrical signals travel in paths that take information to and from the brain and spinal…
Spinal reflexes don’t require input from brain – may be modulated by higher input from brain but integrated in spinal cord…
The spinal cord is an important structure for the communication between the body and the brain since it containing the spinal nerves that are in charge of the motor and sensory pathways. Therefore, a spinal cord injury (SCI) can affect the pathways of these motor and sensory signals depending on the location of the lesion (Kirshblum, Burns, Biering-Sorensen, Donovan, Graves, Jha, & Waring, 2011). A 38-year-old female patient named Frances F. suffered a SCI and became paraplegic after accidentally being shot with a rifle, leaving a gunshot wound by a bullet entering through the dorsal region of her back close to the tenth rib and leaving no exit wound. After the occurrence, the lower limbs of the patient showed no muscle contractions and she was unable to control defecation or urination.…
Reflex circuits harmonize single organs activities, so you don’t have to consciously plan your heart beat and breathing. Reflex circuits are made up of neural circuits, which are the basic building blocks of the nervous system. The neurons transmit signals down axons, and then the signals stimulate the release of neurotransmitters which cross over the synaptic cleft and bind to receptors on organ cells. Chemical neurotransmitters…
The sciatic nerve is the most massive single nerve in the body that bridges the spine and the lower extremities. It is fed by a total of five nerves originating from the spinal cord, transcending the length of the lower spine to the buttocks, branching out, and continuing to the foot. It innervates the skin and muscles of the lower limbs via the tibial and peroneal nerves. It also provides strength to the legs and is responsible for the reflexes there.…
3. Reflex actions arern’t voluntary. They’re automatic and defensive, usually without thought though you may be in a conscious state.…
| Reflexes such as swallowing, rooting reflex, grasp reflex, startle reflex, and walking and standing reflex.…
The dictionary definition of Reflex is “an involuntary or instinctive movement in response to a stimuli” or in the sense of reflection or mirror image. The reflexes on our feet and hands act as mirror images of the body. The term reflexology was coined in 1917 after Russian Ivan Pavlov concluded that health was affected by eternal stimuli, after teaming up with Vladimir Behterev, the term reflexology was found, yet still wasn’t widely used until the 1960’s.…