Textbook Question
a. What is the function of the basal nuclei?
b. Which basal nuclei form the striatum?
c. Which arches over the diencephalon?
37
views
Ch. 12 The Central Nervous System
Hoehn, Haynes, Abbott12th EditionMarieb Human Anatomy & PhysiologyISBN: 9780138242732
Not the one you use?Change textbookSelect a different textbook
Table of contents
- Ch. 1 The Human Body: An Orientation25
- Ch. 2 Chemistry Comes Alive24
- Ch. 3 Cells: The Living Units24
- Ch. 4 Tissue: The Living Fabric19
- Ch. 5 The Integumentary System12
- Ch. 6 Bones and Skeletal Tissues19
- Ch. 7 The Skeleton14
- Ch. 8 Joints7
- Ch. 9 Muscles and Muscle Tissue26
- Ch. 10 The Muscular System25
- Ch. 11 Fundamentals of the Nervous System and Nervous Tissue23
- Ch. 12 The Central Nervous System25
- Ch. 13 The Peripheral Nervous System and Reflex Activity30
- Ch. 14 The Autonomic Nervous System16
- Ch. 15 The Special Senses26
- Ch. 16 The Endocrine System26
- Ch. 17 Blood27
- Ch. 18 The Cardiovascular System: The Heart25
- Ch. 19 The Cardiovascular System: Blood Vessels27
- Ch. 20 The Lymphatic System and Lymphoid Organs and Tissues16
- Ch. 21 The Immune System: Innate and Adaptive Body Defenses27
- Ch. 22 The Respiratory System21
- Ch. 23 The Digestive System31
- Ch. 24 Nutrition, Metabolism, and Energy Balance26
- Ch. 25 The Urinary System26
- Ch. 26 Fluid, Electrolyte, and Acid-Base Balance24
- Ch. 27 The Reproductive System24
- Ch. 28 Pregnancy and Human Development25
- Ch. 29 Heredity11
Hoehn, Haynes, Abbott12th EditionMarieb Human Anatomy & PhysiologyISBN: 9780138242732Not the one you use?Change textbook
Chapter 12, Problem 12
A patient has suffered a cerebral hemorrhage that has caused dysfunction of the precentral gyrus of his right cerebral cortex. As a result:
a. He cannot voluntarily move his left arm or leg.
b. He feels no sensation on the left side of his body.
c. He feels no sensation on his right side.
Verified step by step guidance1
Step 1: Identify the function of the precentral gyrus. The precentral gyrus is the primary motor cortex responsible for voluntary motor control of the contralateral side of the body.
Step 2: Understand the lateralization of brain function. The right cerebral cortex controls voluntary movements on the left side of the body, and the left cerebral cortex controls the right side.
Step 3: Analyze the symptoms related to motor function. Since the patient cannot voluntarily move his left arm or leg, this aligns with damage to the right precentral gyrus affecting motor control on the left side.
Step 4: Consider the sensory symptoms. The precentral gyrus is primarily motor, so loss of sensation (which is processed in the postcentral gyrus) on the left side is unlikely to be caused by damage to the precentral gyrus.
Step 5: Conclude which symptoms are consistent with the lesion. The inability to move the left side voluntarily (a) is expected, but loss of sensation on either side (b or c) is not directly caused by precentral gyrus dysfunction.
Verified video answer for a similar problem:
This video solution was recommended by our tutors as helpful for the problem above.
Video duration:
2mWas this helpful?
Key Concepts
Here are the essential concepts you must grasp in order to answer the question correctly.
Precentral Gyrus and Motor Function
The precentral gyrus, located in the frontal lobe, is the primary motor cortex responsible for voluntary movement control. Damage to this area disrupts motor commands, leading to paralysis or weakness on the opposite side of the body due to the crossing of motor pathways.
Recommended video:
4:31
Primary Motor Cortex & Primary Somatosensory Cortex
Contralateral Control of the Body
Each cerebral hemisphere controls the opposite side of the body. Therefore, injury to the right precentral gyrus affects motor function on the left side, explaining why voluntary movement of the left arm and leg would be impaired.
Recommended video:
3:33Levels of Control in the ANS
Distinction Between Motor and Sensory Functions
The precentral gyrus is involved in motor control, not sensory perception. Sensory information is processed in the postcentral gyrus; thus, damage to the precentral gyrus does not cause loss of sensation, only motor deficits.
Recommended video:
06:04Functional Groups
Related Practice
Textbook Question
All of the following descriptions refer to dorsal column–medial lemniscal ascending pathways except one:
a. They include the fasciculus gracilis and fasciculus cuneatus.
b. They include a chain of three neurons.
c. Their connections are diffuse and poorly localized.
d. They are concerned with precise transmission of one or a few related types of sensory input.
749
views
Textbook Question
What constitutes the blood brain barrier?
1182
views
Textbook Question
List four ways in which the CNS is protected.
1056
views
Textbook Question
A number of brain structures are listed below. If an area is primarily gray matter, write a in the answer blank; if mostly white matter, respond with b.
________ (1) cerebral cortex
________ (2) corpus callosum and corona radiata
________ (3) red nucleus
________ (4) medial and lateral nuclear groups
________ (5) medial lemniscus
________ (6) cranial nerve nuclei
________ (7) spinothalamic tract
________ (8) fornix
________ (9) cingulate and precentral gyri
938
views
Textbook Question
a. What is the advantage of having a cerebrum that is highly convoluted?
b. What term is used to indicate its grooves? Its outward folds?
c. Which groove divides the cerebrum into two hemispheres?
d. What divides the parietal from the frontal lobe? The parietal from the temporal lobe?
940
views