Functional Neuroanatomy Questions
1. A patient has suffered a severe spinal cord injury due to a stab wound; it has damaged the entire left half of a section of her cervical spinal cord. Which of the following would she most likely experience?
- A. Loss of pain sensation on the left side of her body below the damage
- B. Loss of proprioception on the right side of the body below the damage
- C. Loss of movement on the left side of the body below the damage
- D. Loss of tactile discrimination on the right side of the body below the damage
Show Answer
Correct answer: C
The functions indicated in the answer choices are associated with three tracts: the spinothalamic tract (pain/temperature), dorsal columns-medial lemniscus (touch/proprioception), & corticospinal tract (movement). Damage to half of the spinal cord would disrupt all three pathways, but the deficit for the dorsal columns-medial lemniscus and corticospinal tract would be on the same side, while the spinothalamic tract deficit would be on the opposite side, due to where these tracts decussate.
2. This structure, which is the largest bundle of axons in the brain, is sometimes severed as a way of treating epilepsy in patients who don't respond to other treatment approaches:
- A. anterior commissure
- B. corticospinal tract
- C. spinothalamic tract
- D. corpus callosum
Show Answer
Correct answer: D
The corpus callosum is the largest collection of white matter in the brain. It connects the two cerebral hemispheres and permits communication between them. A corpus callosotomy is a procedure where the corpus callosum is severed (typically partially), and it can be done to reduce the ability of seizures to spread from one cerebral hemisphere to the other. See this article for more info:
3. These glial cells are responsible for myelinating neurons in the central nervous system:
- A. Schwann cells
- B. microglia
- C. astrocytes
- D. oligodendrocytes
Show Answer
Correct answer: D
Myelin is an insulating material that covers the axons of most neurons in the nervous system. Oligodendrocytes are the cells responsible for myelinating central nervous system neurons, while Schwann cells myelinate neurons in the peripheral nervous system.
4. A neuron receives most of its information (e.g., in the form of neurotransmitters) at its:
- A. dendrites
- B. cell body (soma)
- C. axon
- D. axon terminals/synaptic boutons
Show Answer
Correct answer: A
Synapses can be formed between any two components of a neuron, but most of a neuron's synapses are found at its dendrites. This is where a neuron receives most of its incoming messages in the form of neurotransmitters and other signaling molecules.
5. Hydrocephalus occurs when cerebrospinal fluid accumulates in the:
- A. thalamus
- B. spinal cord
- C. ventricles
- D. brainstem
Show Answer
Correct answer: C
Hydrocephalus is a condition that involves the accumulation of cerebrospinal fluid (CSF) in the ventricles. It can occur due to excess production of CSF, impaired reabsorption of CSF into the bloodstream, or a blockage in the ventricular system that causes CSF to accumulate.
6. The main distinction between gray matter and white matter in the nervous system is that gray matter has a comparatively high amount of __________, while white matter has a higher amount of __________.
- A. myelinated axons, neuronal cell bodies
- B. dendrites, neuronal cell bodies
- C. neuronal cell bodies, myelinated axons
- D. neuronal cell bodies, dendrites
Show Answer
Correct answer: C
Gray matter is characterized by having a high amount of neuronal cell bodies and fewer myelinated axons. White matter has a high amount of myelinated axons, which give it its white(ish) color.
7. Robert is walking down the street when a large, dangerous-looking dog leaps over a fence and starts chasing him. His heart rate rapidly increases as he begins to run away. Activity in which of these divisions of the nervous system would be most prominent?
- A. sympathetic
- B. parasympathetic
- C. enteric
- D. activity would be equally distributed between all three of these
Show Answer
Correct answer: A
The sympathetic division of the autonomic nervous system is most active during threatening situations, or any situation that requires increased activity of the body. It is involved in what are sometimes called "fight-or-flight" reactions (like Robert was displaying). It increases heart rate and blood flow to muscles to enable them to act, among other functions. See here for a 10-minute video that covers the divisions of the nervous system in depth:
8. Almost all incoming sensory information (olfactory information being an exception) gets sent to this structure before being sent to a primary sensory area in the cerebral cortex for processing:
- A. thalamus
- B. amygdala
- C. hippocampus
- D. hypothalamus
Show Answer
Correct answer: A
The thalamus is sometimes called a "relay station" because it is an important hub in many circuits that carry information to and from the cerebral cortex, and it is a stopping off point for all sensory information (except olfactory information) before that info gets sent to the cortex. The thalamus is much more than just a relay station, though, as it is involved in processing information as well.
9. The name of this structure translates to "little brain," and the structure is thought to contain more than half of the brain's neurons (up to 80%, according to some estimates):
- A. cerebral cortex
- B. cerebellum
- C. cerebrum
- D. cerebral peduncle
Show Answer
Correct answer: B
The word "cerebellum" comes from Latin, and it translates to "little brain." By some estimates, the cerebellum contains up to 80% of the brain's neurons. Part of the reason for this high number of neurons is that the cerebellar cortex is densely packed with very small neurons called granule cells.
10. While various parts of the brain are involved in controlling vital functions, this region has neurons that play especially critical roles in the regulation of heart rate, blood pressure, and respiratory rate:
- A. hippocampus
- B. medulla oblongata
- C. cerebellum
- D. pineal gland
Show Answer
Correct answer: B
The medulla (a region of the brainstem) is involved in a long list of functions, but perhaps the most important among them is the regulation of vital functions. The medulla receives information from receptors in the body about heart rate, blood pressure, and oxygen levels in the blood (among other things). If any of these levels are outside of a desire range, the medulla can adjust cardiac and respiratory function to attempt to return them to where they should be.
11. In neuroanatomy, this term is used to describe a fissure formed due to the folding of the cerebral cortex:
- A. gyrus
- B. cerebral groove
- C. sulcus
- D. cerebral cleft
Show Answer
Correct answer: C
A sulcus (pl. sulci) is a term used in anatomy to refer to a fissure or groove. In neuroanatomy, the term is used to describe the many fissures riddling the surface of the cerebral cortex. It is also used to describe fissures in other nervous system structures, such as the cerebellum and spinal cord. Gyrus (pl. gyri) is a term used to describe the ridges of the cerebral cortex.
12. The majority of the blood supply to the brain is delivered by these arteries:
- A. vertebral
- B. internal carotid
- C. posterior cerebral
- D. spinal
Show Answer
Correct answer: B
The internal carotid arteries travel up the side of the neck and to the brain, supplying the brain with around 70-80% of its blood. The vertebral arteries supply the other 20-30%.
13. The dorsal roots primarily carry which type of information?
- A. sensory
- B. motor
- C. a combination of sensory and motor
Show Answer
Correct answer: A
The dorsal roots enter the posterior side of the spinal cord, carrying sensory information to the spinal cord. The ventral roots leave the anterior side of the spinal cord, carrying motor signals to cause movements.
14. This is the outermost and thickest layer of the meninges:
- A. pia mater
- B. arachnoid mater
- C. dura mater
Show Answer
Correct answer: C
The meninges are a group of membranes that surround the brain and spinal cord, providing protection and support as well as serving a number of other purposes. The outermost and thickest layer of the meninges is the dura mater. It is a tough and fibrous layer that helps protect the brain.
15. This term describes a centrally located group of structures that includes the thalamus, hypothalamus, subthalamus, and epithalamus:
- A. rhombencephalon
- B. telencephalon
- C. prosencephalon
- D. diencephalon
Show Answer
Correct answer: D
The diencephalon is found above the brainstem at the center of the brain and includes the thalamus, hypothalamus, subthalamus, and epithalamus (which consists primarily of the pineal gland and the habenulae).
16. Which component of a synapse below is where neurotransmitters are typically released FROM?
- A. presynaptic membrane
- B. synaptic cleft
- C. postsynaptic membrane
- D. gap junction
Show Answer
Correct answer: A
Neurotransmitters are typically released FROM the presynaptic membrane and INTO the synaptic cleft. They typically bind to receptors on the postsynaptic membrane. Gap junctions (the last answer choice) are regions where neurons communicate at electrical synapses (which don't involve neurotransmitters).
17. The blood-brain barrier helps to keep unwanted substances from passing out of the cerebral bloodstream and into the brain. Which of the following characteristics would you likely see in a substance that is able to cross the blood-brain barrier?
- A. it is a large molecule
- B. it is a complex carbohydrate
- C. it is soluble in lipids
- D. it is an antibiotic drug
Show Answer
Correct answer: C
The blood-brain barrier is a complex that surrounds most of the blood vessels in the brain. It acts as a barrier between the bloodstream and the extracellular space of the brain, allowing only certain substances like water, oxygen, and small lipid-soluble substances to easily cross from the blood into the brain.
18. A patient has a stroke that causes damage confined to the occipital lobe. Which of the following functions would you most expect to see a deficit in?
- A. vision
- B. voluntary movement
- C. taste
- D. the ability to detect the texture of an object by touch alone
Show Answer
Correct answer: A
The visual cortex takes up much of the occipital lobe; it includes the primary visual cortex and the surrounding visual association areas. While a stroke can cause a variety of symptoms, if damage were confined to the occipital lobe, one would expect a visual deficit to be prominent.
19. This deep groove separates the left and right cerebral hemispheres:
- A. central sulcus
- B. corpus callosum
- C. Sylvian fissure
- D. longitudinal fissure
Show Answer
Correct answer: D
The longitudinal fissure is a deep groove that runs along the middle of the brain, separating it into two cerebral hemispheres. It is one of the most recognizable features of the brain.
20. True or False: Neuroimaging evidence suggests that people who are highly artistic tend to utilize their right cerebral hemisphere more than their left, while those who are more logical/analytical tend to use their left cerebral hemisphere more than their right.
- A. True
- B. False
Show Answer
Correct answer: B
While there are some functional differences between the left and right cerebral hemispheres, the idea that someone's personality style corresponds to a greater utilization of one cerebral hemisphere over another is generally regarded as a myth. A 2013 study, for example, looked at the brains of 1,000 people with a variety of personalities, and found no evidence of utilization of one hemisphere over the other.
21. A doctor needs to obtain a sample of cerebrospinal fluid to test for suspected meningitis. Where should she sample the cerebrospinal fluid from?
- A. between the C1 and C6 vertebrae
- B. between the T3 and T6 vertebrae
- C. between the L2 and S2 vertebrae
- D. anywhere along the vertebral column
Show Answer
Correct answer: C
The spinal cord itself ends at L1-L2, but the meningeal layers continue down to the S2 level, as does the subarachnoid space (which contains cerebrospinal fluid). Between the L1/L2 and S2 vertebrae is a region known as the lumbar cistern, which contains cerebrospinal fluid but no spinal cord. Thus, it is safest to sample cerebrospinal fluid from this region, since insertion of a needle doesn't risk damaging the spinal cord.
22. Which of the brain regions below has the most prominent role in the direct regulation of body temperature?
- A. thalamus
- B. hypothalamus
- C. amygdala
- D. hippocampus
Show Answer
Correct answer: B
The hypothalamus plays a direct role in the regulation of body temperature. It constantly monitors the temperature of the body and, when temperature gets too high or too low, enacts mechanisms to bring it back to baseline. For example, if your body is too hot, the hypothalamus can cause perspiration to cool it off. The hypothalamus is involved a long list of other functions as well.
23. Carpal tunnel syndrome is caused by the compression of which nerve?
- A. Ulnar nerve
- B. Median nerve
- C. Radial nerve
- D. Axillary nerve
Show Answer
Correct answer: B
Carpal tunnel syndrome is a common condition caused by the compression of the median nerve, which carries sensations from the thumb, index finger, middle finger, and part of the ring finger—primarily on the palm side of the hand—as well as controls most of the muscles in the thumb, some muscles in the forearm that help with finger and wrist movements, and muscles in the index and middle fingers.
24. This extension of a neuron is responsible for carrying action potentials from one end of a neuron to the other:
- A. dendrites
- B. soma/cell body
- C. axon
- D. axon terminal
Show Answer
Correct answer: C
The axon is the extension of a neuron that carries an action potential from one end of a neuron to the other. The axon conducts action potentials away from the soma/cell body and toward the axon terminals.
25. A tumor causes the cerebral aqueduct to become blocked, allowing very little cerebrospinal fluid to flow through it. What ventricle or ventricles will likely become enlarged, potentially resulting in hydrocephalus?
- A. only the lateral ventricles
- B. only the third ventricle
- C. the third ventricle and both lateral ventricles
- D. all four ventricles (both lateral, third, and fourth)
Show Answer
Correct answer: C
The cerebral aqueduct connects the third ventricle with the fourth ventricle. Cerebrospinal fluid (CSF) is produced in all of the ventricles and flows out through the fourth ventricle into the subarachnoid space. If the cerebral aqueduct is blocked, CSF would continue to be produced in the lateral and third ventricles, but it would have no way of reaching the fourth ventricle to exit the ventricular system. Thus, it would accumulate in the third ventricle and both lateral ventricles.
26. Damage to the anterior horn of the cervical spinal cord would most likely result in which of the following deficits?
- A. an inability to perceive touch sensations in the upper limbs
- B. weakness or paralysis in the upper limbs
- C. difficulty producing speech
- D. loss of proprioceptive sense throughout the body
Show Answer
Correct answer: B
The anterior horn contains the cell bodies of motor neurons that activate skeletal muscle to cause movement. Damage to the anterior horn typically causes movement deficits, such as paralysis, weakness, and hyporeflexia; since the damage is in the cervical cord, it would affect the upper limbs.
27. The name for this brainstem structure is Latin for "bridge," and it was so named because it resembles a bridge that connects the two hemispheres of the cerebellum:
- A. pons
- B. midbrain
- C. medulla oblongata
- D. substantia nigra
Show Answer
Correct answer: A
The pons is a major division of the brainstem. Pons is Latin for "bridge"; the structure was given its name by the Italian anatomist Costanzo Varolio, who thought that the most conspicuous portion of the pons resembled a bridge that connected the two cerebellar hemispheres.
28. A woman with the initials of S.M. is considered a famous case in neuroscience and medical history, as she has almost completely lost her ability to experience fear after damage to this brain structure:
- A. amygdala
- B. hippocampus
- C. thalamus
- D. cerebellum
Show Answer
Correct answer: A
S.M. is a well-known medical case who has almost completely lost the ability to experience fear after a rare genetic disorder caused the deterioration of both of her amygdalae. Her case helped us to recognize the importance of the amygdala in fearful emotions, although it is now recognized to play a role in positive emotions as well.
29. According to our best estimates, how many neurons are in an average brain?
- A. 500 million
- B. 24 billion
- C. 86 billion
- D. 100 trillion
Show Answer
Correct answer: C
Estimates have varied over time, but our current best estimate of the number of neurons in the brain is 86 billion (on average). Neurons are not distributed evenly throughout the brain, and some areas (e.g., cerebellum) have much more than others.
30. How is hydrocephalus typically treated?
- A. With drugs that increase the production of cerebrospinal fluid (CSF)
- B. With a device called a shunt that drains CSF from the ventricles
- C. By reducing fluid intake to reduce the amount of CSF produced
- D. There is no accepted treatment for hydrocephalus
Show Answer
Correct answer: B
A cerebral shunt is the most common treatment for hydrocephalus. A shunt system consists of a plastic tube connected to a valve and a catheter. One end of the catheter is placed in a ventricle where CSF is accumulating, and the other is typically placed in the abdominal cavity. The shunt diverts CSF to the abdominal cavity, where it can safely drain and be absorbed into the bloodstream.
