WBR0578

Author	[[PageAuthor::Rim Halaby, M.D. [1] (Reviewed by Yazan Daaboul, M.D.)]]
Exam Type	ExamType::USMLE Step 1
Main Category	MainCategory::Pathophysiology
Sub Category	SubCategory::Neurology
Prompt	[[Prompt::A 71-year-old right-handed man with a past medical history significant for coronary artery disease and hypertension presents to the emergency department for acute-onset right arm weakness and speech difficulty. The patient is not able to speak in full sentences and answers by saying: "Ummm...Ummm..Not move..Ummm arrr...arm". Whenever the physician asks him a question, the patient tries to answer by using hand gestures. Which of the following brain regions is most likely responsible for the patient's speech dysfunction?]]
Answer A	AnswerA::Superior temporal gyrus
Answer A Explanation	[[AnswerAExp::Wernicke's aphasia is a speech dysfunction characterized by impaired comprehension, intact speech fluency, and impaired repetition. It results from damage to the superior temporal gyrus. Wernicke's aphasia is also known as sensory or receptive aphasia.]]
Answer B	AnswerB::Inferior frontal gyrus
Answer B Explanation	[[AnswerBExp::Broca's aphasia is a speech dysfunction characterized by intact comprehension, impaired speech fluency, and impaired repetition. It results from damage to the inferior frontal gyrus. Broca's aphasia is also known as motor or expressive aphasia.]]
Answer C	AnswerC::Superior temporal and frontal gyri
Answer C Explanation	[[AnswerCExp::Global aphasia is a speech dysfunction characterized by impaired comprehension, impaired speech fluency, and impaired repetition. It results from damage to a larger area of the brain that involves the superior temporal and inferior frontal gyri.]]
Answer D	AnswerD::Arcuate fasiculus
Answer D Explanation	[[AnswerDExp::Conduction aphasia is a speech dysfunction characterized by intact comprehension, intact speech fluency, and impaired repetition. It results from damage to the arcuate fasciculus.]]
Answer E	AnswerE::Area between the supplementary motor area and the frontal perisylvian speech zone
Answer E Explanation	[[AnswerEExp::Transcortical motor aphasia is a speech dysfunction characterized by impaired comprehension, impaired speech fluency, and intact repetition. It results from damage to the area between the supplementary motor area and the frontal perisylvian speech zone.]]
Right Answer	RightAnswer::B
Explanation	[[Explanation::The patient's sudden-onset right side weakness along with speech difficulty is consistent with a stroke that involves the middle cerebral artery (MCA). The patient seems to understand what the physician is asking but is finding difficulty articulating the words. The patient's intact comprehension and impaired fluency of speech result from involvement of the Broca's area in the left dominant frontal lobe. Involvement of the left frontal lobe also explains the contralateral arm weakness. There are several types of aphasia: Wernicke's aphasia: impaired comprehension, intact speech fluency, and impaired repetition. Broca's aphasia: intact comprehension, impaired speech fluency, and impaired repetition. Global aphasia: impaired comprehension, impaired speech fluency, and impaired repetition. Conduction aphasia: intact comprehension, intact speech fluency, and impaired repetition. Shown below is an image that depicts the different regions involved in aphasias. Educational Objective: Broca's aphasia is a speech dysfunction characterized by intact comprehension, impaired speech fluency, and impaired repetition. It results from damage to the inferior frontal gyrus. References: First Aid 2014 page 457]]
Approved	Approved::No
Keyword	WBRKeyword::Aphasia, WBRKeyword::Broca's aphasia, WBRKeyword::Frontal lobe, WBRKeyword::Stroke
Linked Question	Linked::
Order in Linked Questions	LinkedOrder::