No
Yes, paraplegics can still have knee jerk reflexes. The knee jerk reflex is controlled by the lower part of the spinal cord, which may still function even if there is paralysis or impairment in the upper part of the cord. However, the presence or absence of knee jerk reflexes does not determine the extent of paralysis in paraplegics.
The reflexes that have one thing in common are the knee, ankle, plantar jerk, biceps, and triceps. They are all governed by reflex arcs in the spine.
Knee jerk and Achilles reflexes are crucial for maintaining balance and stability while walking. The knee jerk reflex helps stabilize the leg and maintain posture by automatically adjusting muscle tension in response to changes in the body's position. Similarly, the Achilles reflex aids in controlling the ankle's movements, ensuring a smooth and coordinated gait. Together, these reflexes enable quick adjustments, preventing falls and facilitating efficient locomotion.
Involuntary reflexes, such as the knee-jerk reflex or pupillary reflex, are not subject to conscious control. These automatic responses are typically controlled by the spinal cord or brainstem without involvement of higher brain regions.
The knee-jerk and Achilles reflexes help in maintaining balance and stability while walking by providing feedback to the brain about the muscle tone and tension in the lower limbs. They also help in preventing injury by quickening the reflex response to unexpected changes in terrain or position.
Research (done some decades back, actually) has found that the fastest reflexes are among "Olympic" weightlifters (i.e. those who do snatch, clean & jerk, and their associated lifts).
A. abdominal reflex B. Achilles jerk D. corneal reflex E. crossed extensor reflex F. gag reflex G. patellar reflex H. plantar reflex
Intrinsic reflexes, also known as innate or unlearned reflexes, are automatic responses to specific stimuli that are hardwired in an organism's nervous system, such as the knee-jerk reaction. In contrast, learned reflexes are acquired through experience and practice, involving a more complex interaction with the environment, such as riding a bicycle or playing a musical instrument. While intrinsic reflexes are typically quick and involuntary, learned reflexes require cognitive processing and can be modified over time.
Their body reflexes automatically cause the leg, from the knee down, to jerk upwards.
The statement "The patellar knee jerk reflex is controlled by the brain" is not correct. The patellar knee jerk reflex is actually a spinal reflex, meaning it does not involve the brain in its initial response.
Reflexes, such as the knee-jerk reflex, are behaviors that are not learned and occur automatically in response to a specific stimulus. These reflexes are typically controlled by the spinal cord and do not require higher brain involvement or learning.
Inborn or intrinsic reflexes are automatic, involuntary responses that occur without conscious thought. These reflexes are typically present from birth and are essential for survival, helping to protect the body from harm or danger. Examples include the knee-jerk reflex and blinking in response to a bright light.