Nokea
What is the consequence for the ability of motor neurons to find their correct targets, if a section of the spinal cord is rotated, so that the antero-posterior axis is reversed?
- A. Anterior motor neurons enter the limb in a bundle in the posterior instead of the anterior, but then take novel pathways to find the correct anterior muscles to innervate.
- B. Anterior motor neurons enter the limb in a bundle in the posterior instead of the anterior, and follow pathways intended for posterior neurons to make contacts with posterior muscles.
- C. Anterior motor neurons change their course to enter the limb in the anterior, but take their usual pathways to find the correct anterior muscles.
- D. The motor neurons grow over to the other side of the spinal cord and resume their normal pathways into muscles on their normal side of the body.
Correct Answer: B
Rationale: When the antero-posterior axis of the spinal cord is reversed, motor neurons follow their intrinsic programming and enter the limb in the reversed position. They then innervate muscles based on their new position, leading to incorrect connections. This demonstrates the importance of spatial cues in guiding motor neurons to their correct targets.
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With regard to myotomal nerve supply
- A. opponens pollicis is C8
- B. shoulder abduction is C5, 6
- C. ankle plantar flexion is L4, 5
- D. elbow extension is C7, 8
Correct Answer: B
Rationale: Shoulder abduction is primarily controlled by the C5 and C6 nerve roots, which innervate the deltoid and supraspinatus muscles.
Which of the following is an incorrect pairing?
- A. norepinephrine dilates the pupil
- B. epinephrine increases blood pressure
- C. acetylcholine decreases digestion
- D. norepinephrine increases heart rate
Correct Answer: C
Rationale: The correct answer is C because acetylcholine actually increases digestion by stimulating the release of digestive enzymes and promoting peristalsis. A is incorrect because norepinephrine dilates the pupil, B is incorrect because epinephrine does increase blood pressure, and D is incorrect because norepinephrine does increase heart rate. Remember, acetylcholine is primarily responsible for parasympathetic responses, which include rest and digest functions.
A treatment designed to aid production and comprehension of speech is known as group communication treatment. A study by Elman & Berstein-Ellis (1999) showed:
- A. No improvement in functional communication compared with patients not receiving structured treatment.
- B. Significantly more improvement in functional communication compared with patients not receiving structured treatment.
- C. Declined in functional communication compared with patients not receiving structured treatment.
- D. An improvement in non-targetted factors.
Correct Answer: B
Rationale: Group communication treatment is a therapeutic approach aimed at improving speech production and comprehension in individuals with language disorders, such as aphasia. A study by Elman and Berstein-Ellis (1999) demonstrated that this treatment led to significant improvements in functional communication compared to individuals who did not receive structured therapy. The group setting provides opportunities for social interaction and practice, enhancing the effectiveness of the treatment.
Which of the following is not a branch of the trigeminal nerve?
- A. Supraorbital nerve
- B. Great auricular nerve
- C. Mental nerve
- D. Lacrimal nerve
Correct Answer: B
Rationale: The great auricular nerve is a branch of the cervical plexus (C2-C3), not the trigeminal nerve. It supplies sensation to the skin over the parotid gland and ear.
Which of the following will not worsen PD symptoms?
- A. Haloperidol
- B. Metoclopramide
- C. Prochlorperazine
- D. Rasagiline
Correct Answer: D
Rationale: Rasagiline is a MAO-B inhibitor used to treat PD and does not worsen symptoms, unlike dopamine antagonists like haloperidol and metoclopramide.