The Babinski reflex is a somatic reflex seen in infants. When the side of the foot is stroked, the toes spread apart. Another example of a somatic reflex is the ankle-jerk reflex, which causes the ankle to bend the foot towards the ground when the Achilles tendon is tapped.Know More
Somatic reflexes are movements of body parts that result nearly instantly when a certain stimulus is delivered. Reflexes are able to occur so quickly because the stimuli that cause them are not processed in the brain. Rather, the nerve impulse generated by the stimulus is relayed only to the spinal cord. A motor nerve impulse, which signals for the muscles to react in a certain way, is then sent back from the spinal cord to the muscle.
Humans display many different reflexes. The biceps reflex causes the forearm to jerk when the biceps brachii is tapped with a hammer. The corneal reflex causes a person to blink when the cornea of the eye is touched, and the knee-jerk reflex causes the lower leg to kick outward when the patellar tendon just beneath the knee cap is struck. Blushing is another reflex; the face turns red when a person experiences embarrassment or shame.Learn more about Nerves
Cerebrospinal fluid is a clear, colorless fluid found in the subarachnoid spaces in the cranial cavity, where it functions as a shock absorber for the delicate tissues of the brain, according to Fluids and Barriers of the CNS. Cerebrospinal fluid also removes waste in the absence of a lymphatic system.Full Answer >
The brain is protected by connected bony plates in the head known as the skull. It is also protected by the meninges, a three layer membrane.Full Answer >
The optic nerve, also called cranial nerve II or the second cranial nerve, is responsible for carrying images from the eyes to the brain. The transfer of visual information begins in the retina and travels to the brain's visual centers with the help of electrical impulses.Full Answer >
Having many noticeable veins in your feet may be a symptom of varicose veins. Veins enlarge due to damage to veins in the feet or increased pressure in the leg veins, but it is rarely a serious problem. Furthermore, it is often genetic.Full Answer >