The Vestibular Sense & Gaze
ByAdmin
Week- 6 The Vestibular Sense & Gaze >>> Understanding the Brain: The Neurobiology of Everyday Life
1. Imagine that a person is holding a stone hanging from a string. As the person jumps straight up, the stone lags behind, pulling the string taut. As that person falls back to earth, the stone lags behind, floating upward on a lax string. Which of the following is true in a person accelerating downward as they fall back to earth? Check all that apply.
1 point
2. Which of the following actions would stimulate the otoconial masses? Check all that apply.
1 point
3. Which of the following groups of symptoms would you expect from damage to the semicircular canals? Choose one answer.
1 point
4. Which of the following will lead to a hair cell changing its membrane potential from rest (about -40 mV) to a more depolarized potential such as -20 mV? Check all that apply.
1 point
5. We talked about how visual information comes into the vestibular nuclei. In addition, somatosensory information such as touch and proprioception (information from joints and muscles) also reaches the vestibular nuclei. Vestibular nuclear neurons gain information from somatosensory inputs just as they do from visual inputs. So if you stood on a moving belt with your eyes closed and held out your hand and you felt the wall slowly moving, you would not know if you were moving or if the wall were moving. Now with this information, imagine an older person who is beginning to have balance issues. Under which of the following conditions will this person feel more balanced? Check all that apply.
1 point
6. Imagine what happens as we walk or run along uneven ground. Our head accelerates and decelerates in many different directions with every stride. The result of this will include which of the following? Check all that may occur.
1 point
7. Consider that you turn your head quickly to the right. As it turns out, when you generate such a movement, the vestibular system does not react to the head acceleration involved. This is because a copy of the motor command is sent to the vestibular nucleus and this message is used to cancel the input from the inner ear. In other words, the vestibular system ignores head accelerations that can be predicted as the expected result of an intentional movement. So consider that as you turn your head to the right at time A, your face hits a door, causing a rapid deceleration to the left at time B. Which of the following vestibular responses will occur?
1 point
8. Throughout evolutionary time, animals have propelled themselves. In other words, animals moved only if they moved themselves using their own muscles. However, now we have vehicles that can carry us about without any muscular effort from us. This has led to the phenomenon of motion sickness in which nausea results from a mismatch between vestibular and visual inputs. With this information which of the following is most likely to give rise to motion sickness?
1 point
9. You are pressed for time but really want to exercise while also staying hydrated. So you end up doing biceps presses while filling up your water bottle. As your body moves with each repetition of the biceps press, which of the following stays the most steady? Choose one answer.
1 point
10. You are searching for your cat who has crawled into the smallest possible space in your apartment. You hear her meow and spot her. To get a better look at her, you roll your head to the right (so that your head is laying on your right shoulder). As you roll your head to the right, and keep looking at your cat, your eyes move in which of the following ways? Choose one answer.
1 point
11. A person suddenly becomes unresponsive, suggestive of a stroke. In order to quickly assess the severity of the stroke, the emergency room physician holds the person’s head in her hands and quickly rotates the head to the right. The eyes move to the left so that gaze remains straight ahead. When the physician rotates the head to the left, the eyes move to the right, keeping gazing straight ahead. From this information which of the following are clearly working normally? Check all that apply.
1 point
12. You are reading a book while relaxing in a reclining chair. Your head is resting on pillows and is steady and the book is resting on your knees and is also steady. Which of the following areas are involved as you read the book? Check all that apply.
1 point
