1.
Which of these reflexes is controlled by the brainstem?
Correct Answer
A. Oculo-cepHalic Reflex
Explanation
The oculo-cephalic reflex, also known as the doll's eye reflex, is controlled by the brainstem. This reflex involves the movement of the eyes in response to the movement of the head. When the head is turned to one side, the eyes will move in the opposite direction to maintain fixation on a target. This reflex is mediated by the brainstem, specifically the vestibular nuclei and the oculomotor nuclei, which receive and process information from the inner ear and send signals to the muscles that control eye movement.
2.
What is the reflex of eye movement known as?
Correct Answer
A. Oculo-cepHalic Reflex
Explanation
The reflex of eye movement is known as the oculo-cephalic reflex.
3.
Which of these is a ear reflex?
Correct Answer
D. Vestibulo-ocular reflex
Explanation
The vestibulo-ocular reflex is a reflex that helps maintain stable vision by coordinating eye movements with head movements. This reflex allows the eyes to move in the opposite direction of head movement, which helps to keep the visual field stable. This reflex is essential for tasks such as reading while walking or maintaining balance while moving the head.
4.
What does the eye reflex stabilize on the retina?
Correct Answer
A. Images
Explanation
The eye reflex stabilizes images on the retina. When light enters the eye, it passes through the lens and is focused onto the retina, which contains light-sensitive cells called photoreceptors. These photoreceptors detect the incoming light and send signals to the brain, allowing us to see. The eye reflex, also known as the oculomotor reflex, helps to keep the images steady on the retina by making small adjustments to the position of the eyes. This ensures that the images remain clear and in focus, even when the head or body is moving.
5.
What is a caloric reflex?
Correct Answer
D. Vestibulo-ocular reflex
Explanation
The vestibulo-ocular reflex is a reflex that helps maintain stable vision during head movements. It works by coordinating eye movements with head movements, allowing the eyes to remain focused on a target even when the head is in motion. This reflex is important for maintaining clear vision and preventing blurriness or double vision when the head is moving.
6.
What direction does the brainstem reflex usually lead the eye movement to the head movement?
Correct Answer
A. Opposite
Explanation
The brainstem reflex usually leads the eye movement in the opposite direction of the head movement. This reflex is known as the vestibulo-ocular reflex (VOR) and it helps to stabilize vision during head movements. When the head turns to one side, the brainstem sends signals to the eye muscles to move the eyes in the opposite direction, ensuring that the image on the retina remains stable. This allows us to maintain clear vision while moving our head.
7.
Which of these is a way to test the reflex?
Correct Answer
B. Halmagyi-Curthoys-test
Explanation
The Halmagyi-Curthoys test is a way to test the reflex. This test is used to assess the function of the vestibular system, which is responsible for balance and spatial orientation. It involves the rapid movement of the head to stimulate the vestibular system and elicit reflexive eye movements called nystagmus. By observing the direction and intensity of the nystagmus, healthcare professionals can evaluate the integrity of the vestibular system and diagnose any vestibular disorders.
8.
What sign does a negative “doll’s eyes” of a comatose patient’s show?
Correct Answer
B. Not Intact Brainstem
Explanation
A negative "doll's eyes" sign in a comatose patient indicates that the brainstem is not intact. The doll's eyes reflex is a test that involves moving the patient's head from side to side. In a normal response, the eyes will move in the opposite direction of the head movement. However, in a patient with a non-intact brainstem, the eyes will remain fixed in one position and not move in the opposite direction. This indicates dysfunction or damage to the brainstem, which is responsible for controlling eye movements.
9.
What corrects the eyes movement among these?
Correct Answer
A. Nystagmus
Explanation
Nystagmus is a condition that causes involuntary and repetitive eye movements. It can result in rapid, jerking movements of the eyes, making it difficult to maintain a steady gaze. The other options listed - chlorophyll, chloroform, and ricin - are unrelated to the movement of the eyes and do not correct or affect nystagmus in any way.
10.
What direction of eye movement does pouring of warm water into the left ear lead to?
Correct Answer
A. Left
Explanation
Pouring warm water into the left ear leads to leftward eye movement. This is because the vestibular system, which is responsible for maintaining balance and spatial orientation, is stimulated by the warm water. The stimulation of the left ear causes the vestibular system to send signals to the brain, which in turn triggers eye movement towards the left side.