Podcast
Questions and Answers
A patient presents with motor aphasia following a stroke. Lesion localization, considering Brodmann's areas, should prioritize investigation of which specific region?
A patient presents with motor aphasia following a stroke. Lesion localization, considering Brodmann's areas, should prioritize investigation of which specific region?
- Area 17 in the occipital lobe, concerned with visual reception.
- Area 44 in the dominant hemisphere, responsible for motor speech production. (correct)
- Area 22 in the dominant hemisphere, involved in auditory association.
- Area 39 in the parietal lobe, associated with reading and visual symbol recognition.
A patient exhibits contralateral paralysis primarily affecting the lower limb, coupled with urinary and fecal incontinence. Which specific anatomical structure is most likely implicated?
A patient exhibits contralateral paralysis primarily affecting the lower limb, coupled with urinary and fecal incontinence. Which specific anatomical structure is most likely implicated?
- The superior temporal gyrus within the temporal lobe.
- The precentral gyrus in the frontal lobe.
- The post-central gyrus in the parietal lobe.
- The paracentral lobule on the medial surface of the superior frontal gyrus. (correct)
Following a traumatic brain injury, a patient demonstrates impaired recognition and recall of sounds, despite intact auditory sensation. Which cortical area is most likely compromised, correlating Wernicke's area?
Following a traumatic brain injury, a patient demonstrates impaired recognition and recall of sounds, despite intact auditory sensation. Which cortical area is most likely compromised, correlating Wernicke's area?
- Area 41 and 42 of the temporal lobe.
- Area 4 of the frontal lobe.
- Area 21 and 22 of the temporal lobe. (correct)
- Area 17 of the occipital lobe.
A patient reports the inability to perform previously learned, complex motor tasks, despite exhibiting normal strength and sensation. Where might a lesion be suspected?
A patient reports the inability to perform previously learned, complex motor tasks, despite exhibiting normal strength and sensation. Where might a lesion be suspected?
Which of the following scenarios would least correlate with lesions to the prefrontal cortex (areas 9, 10, and 11) bilaterally?
Which of the following scenarios would least correlate with lesions to the prefrontal cortex (areas 9, 10, and 11) bilaterally?
A patient experiences a diminished ability to execute voluntary conjugate eye movements. What lesion location would most likely cause this deficit?
A patient experiences a diminished ability to execute voluntary conjugate eye movements. What lesion location would most likely cause this deficit?
A lesion in the posterior-inferior portion of the parietal lobe in the dominant hemisphere would most likely result in?
A lesion in the posterior-inferior portion of the parietal lobe in the dominant hemisphere would most likely result in?
A patient presents with contralateral hypertonia and exaggerated deep reflexes. What specific area is most likely affected?
A patient presents with contralateral hypertonia and exaggerated deep reflexes. What specific area is most likely affected?
Which neural structure is responsible for the integration of sensory information and its association with emotional states?
Which neural structure is responsible for the integration of sensory information and its association with emotional states?
In an anatomy class, a medical student is asked to identify the structure that contains the cell bodies of lower motor neurons innervating the muscles of the lower extremities. Which location should they specify?
In an anatomy class, a medical student is asked to identify the structure that contains the cell bodies of lower motor neurons innervating the muscles of the lower extremities. Which location should they specify?
Which description accurately characterizes the anatomical termination of the spinal cord in adults?
Which description accurately characterizes the anatomical termination of the spinal cord in adults?
During a neurosurgical procedure, a surgeon encounters a collection of nerve roots extending inferiorly from the conus medullaris. What is the correct anatomical designation for this structure?
During a neurosurgical procedure, a surgeon encounters a collection of nerve roots extending inferiorly from the conus medullaris. What is the correct anatomical designation for this structure?
During a neurological examination, a physician notes that the patient has lost the ability to recognize familiar faces, despite having intact vision. This condition is most likely the result of damage to which region?
During a neurological examination, a physician notes that the patient has lost the ability to recognize familiar faces, despite having intact vision. This condition is most likely the result of damage to which region?
In the event of a complete spinal cord transection at the level of the first lumbar vertebra (L1), which anatomical structure would most likely remain intact and functional?
In the event of a complete spinal cord transection at the level of the first lumbar vertebra (L1), which anatomical structure would most likely remain intact and functional?
What functional deficits would most likely be observed in a patient following localized damage to the cerebellum?
What functional deficits would most likely be observed in a patient following localized damage to the cerebellum?
A 65-year-old male with a history of hypertension presents to the emergency department with sudden onset of right-sided hemiplegia and difficulty speaking. A CT scan reveals an infarct in the left middle cerebral artery (MCA) territory. Which specific area is most likely affected?
A 65-year-old male with a history of hypertension presents to the emergency department with sudden onset of right-sided hemiplegia and difficulty speaking. A CT scan reveals an infarct in the left middle cerebral artery (MCA) territory. Which specific area is most likely affected?
A researcher is tracing the origin of the corticospinal tract. Where would the researcher expect to find the upper motor neuron (UMN) cell bodies?
A researcher is tracing the origin of the corticospinal tract. Where would the researcher expect to find the upper motor neuron (UMN) cell bodies?
A patient exhibits agraphia and aphasia. What scenario explains this?
A patient exhibits agraphia and aphasia. What scenario explains this?
A patient demonstrates visual agnosia for familiar objects, but possesses intact visual acuity and linguistic capabilities. Which location would most likely be affected?
A patient demonstrates visual agnosia for familiar objects, but possesses intact visual acuity and linguistic capabilities. Which location would most likely be affected?
A patient exhibits an inability to recognize objects by touch (astereognosis) and impaired position sense (proprioception) in the right upper limb. Anatomically where is the lesion for this patient?
A patient exhibits an inability to recognize objects by touch (astereognosis) and impaired position sense (proprioception) in the right upper limb. Anatomically where is the lesion for this patient?
A patient is diagnosed with a lesion localized to the anterior part of the precentral gryus. What associated symptom best corresponds to this condition?
A patient is diagnosed with a lesion localized to the anterior part of the precentral gryus. What associated symptom best corresponds to this condition?
Following a stroke, a patient demonstrates an inability to write, despite being able to read, speak, and understand language. Lesion location is indicated at what site?
Following a stroke, a patient demonstrates an inability to write, despite being able to read, speak, and understand language. Lesion location is indicated at what site?
A patient with a history of temporal lobe epilepsy reports experiencing olfactory hallucinations, particularly unpleasant odors. This is most likely a result of what?
A patient with a history of temporal lobe epilepsy reports experiencing olfactory hallucinations, particularly unpleasant odors. This is most likely a result of what?
A patient presents with impaired word finding and difficulty in the storage or recall of complex ideas of speech. Which location is most commonly associated with this?
A patient presents with impaired word finding and difficulty in the storage or recall of complex ideas of speech. Which location is most commonly associated with this?
Which primary function is served by the prefrontal cortex (areas 9, 10, and 11)?
Which primary function is served by the prefrontal cortex (areas 9, 10, and 11)?
What accurately describes the composition of the spinal cord?
What accurately describes the composition of the spinal cord?
A cross section of the spinal cord would bear structural similarities in what shape?
A cross section of the spinal cord would bear structural similarities in what shape?
If the anterior spinothalamic tract were severed, what symptom would this be associated with?
If the anterior spinothalamic tract were severed, what symptom would this be associated with?
Damage to which area will inhibit muscle tone and the deep reflexes on the opposite side of the body?
Damage to which area will inhibit muscle tone and the deep reflexes on the opposite side of the body?
Which of the following best desribes the brainstem?
Which of the following best desribes the brainstem?
The corticospinal tract has all of the following components, except:
The corticospinal tract has all of the following components, except:
Which cortical region is vital for the immediate processing of bodily sensations received from the periphery?
Which cortical region is vital for the immediate processing of bodily sensations received from the periphery?
A lesion involving only the superior temporal gyrus would MOST likely result in?
A lesion involving only the superior temporal gyrus would MOST likely result in?
What is the function of the paracentral lobule?
What is the function of the paracentral lobule?
A lesion in the spinal cord that damages the lateral corticospinal tract is likely to have what effect?
A lesion in the spinal cord that damages the lateral corticospinal tract is likely to have what effect?
The lower lumbar spinal cord segments include anatomically what main structure?
The lower lumbar spinal cord segments include anatomically what main structure?
What is TRUE regarding the spinal nerve roots?
What is TRUE regarding the spinal nerve roots?
Why are the meninges, cerebrospinal fluid, and network of veins and arteries important?
Why are the meninges, cerebrospinal fluid, and network of veins and arteries important?
If a neurologist suspects damage to the superior cerebellar peduncle, what symptomology should they suspect?
If a neurologist suspects damage to the superior cerebellar peduncle, what symptomology should they suspect?
In an individual presenting with new onset alexia, which area should a physician suspect as the primary location of neurological insult?
In an individual presenting with new onset alexia, which area should a physician suspect as the primary location of neurological insult?
Which area functions as a higher function that associates higher though with emotional states?
Which area functions as a higher function that associates higher though with emotional states?
Flashcards
Central Nervous System
Central Nervous System
The central nervous system consists of the intracranial part (cerebrum, brain stem, cerebellum) and the spinal part (spinal cord).
Cerebrum Lobes
Cerebrum Lobes
The cerebrum is divided into two hemispheres by a longitudinal fissure, each containing four lobes: Frontal, Temporal, Parietal, and Occipital.
Basal Structures
Basal Structures
Located at the base of each cerebral hemisphere, these are groups of nuclei within the white matter: Basal ganglia, Thalamus, Hypothalamus, Subthalamus.
Motor area (area 4)
Motor area (area 4)
Signup and view all the flashcards
Premotor area (area 6)
Premotor area (area 6)
Signup and view all the flashcards
Eye Movement Area (area 8)
Eye Movement Area (area 8)
Signup and view all the flashcards
Broca's area (area 44)
Broca's area (area 44)
Signup and view all the flashcards
Exner's area (area 45)
Exner's area (area 45)
Signup and view all the flashcards
Pre-frontal area (areas 9, 10, 11)
Pre-frontal area (areas 9, 10, 11)
Signup and view all the flashcards
Paracentral lobule
Paracentral lobule
Signup and view all the flashcards
Auditory sensory area (area 41, 42)
Auditory sensory area (area 41, 42)
Signup and view all the flashcards
Auditory Associative Area
Auditory Associative Area
Signup and view all the flashcards
Visual Associative Area
Visual Associative Area
Signup and view all the flashcards
Cortical sensory area (areas 1, 2, 3)
Cortical sensory area (areas 1, 2, 3)
Signup and view all the flashcards
Angular gyrus (area 39)
Angular gyrus (area 39)
Signup and view all the flashcards
Supramarainal gyrus (area 37)
Supramarainal gyrus (area 37)
Signup and view all the flashcards
Brain Stem Components
Brain Stem Components
Signup and view all the flashcards
Cerebellum
Cerebellum
Signup and view all the flashcards
Spinal Cord
Spinal Cord
Signup and view all the flashcards
Cauda Equina
Cauda Equina
Signup and view all the flashcards
Study Notes
Anatomy and Physiology of the Central Nervous System
- The lecture aims to enable students to identify parts of the central nervous system (CNS), recognize their functions, define muscle tone and its neurophysiological basis, and compare upper and lower motor neuron lesions.
Central Nervous System Components
- The CNS is divided into the intracranial and spinal parts.
- The intracranial part includes the cerebrum, brain stem, and cerebellum.
- The spinal part consists of the spinal cord.
Cerebrum
- The cerebrum is divided by a longitudinal fissure into two hemispheres.
- Each hemisphere contains four lobes: frontal, temporal, parietal, and occipital.
- At the base of each cerebral hemisphere, there are several groups of nuclei, situated at various levels within the white matter.
- These are the basal ganglia, thalamus, hypothalamus, and subthalamus
Frontal Lobe
- The motor area (area 4) is located in the floor of the central sulcus and the posterior part of the precentral gyrus.
- Its function involves initiating voluntary motor activity on the opposite side of the body via the pyramidal tract, with the body represented upside down.
- Lesions in the motor area can lead to contralateral paralysis, usually affecting one limb (monoplegia).
- The premotor area (area 6) is located in the anterior part of the precentral gyrus and partly supplies tracts and extra fibers.
- Lesions in the premotor area can result in contralateral hypertonia and exaggerated deep reflexes.
- The area for voluntary conjugate eye movements (area 8) is located in the posterior part of the middle frontal gyrus.
- It functions in voluntary conjugate eye movement to the opposite side. This involves reading a line of text. The movement is rapid(saccadic).
- Lesions in the motor area can cause paralysis of conjugate eye movement to the side opposite the lesion.
- Broca's area (area 44) is located in the posterior part of the inferior frontal gyrus of the dominant hemisphere and functions as a motor center for speech.
- Lesions to Broca's area cause motor (expressive) aphasia, where the patient cannot express ideas in spoken words.
- Exner's area (area 45) is adjacent to area 44 in the dominant hemisphere and is the center for writing.
- Lesions in Exner's area cause agraphia, where the patient cannot express ideas in written words.
- The prefrontal area (areas 9, 10, and 11) is in the anterior part of the frontal lobe and its adjacent inferior surface.
- This area functions as a higher center for mentality, personality, and behavior; furthermore, it inhibits primitive reflexes.
- Lesions to the area can cause mentality, personality, and behavioral changes like a lack of attention and judgment, disinterest in people and surroundings, and lack of personal hygiene, potentially ending in dementia, with the reappearance of primitive reflexes.
- The paracentral lobule is on the medial surface of the superior frontal gyrus, adjacent to the foot and leg area.
- The lobule functions in the cortical inhibition/control of bladder and bowel voiding.
- A lesion here can lead to incontinence of urine and feces.
Temporal Lobe
- The auditory sensory area (areas 41 and 42) is located in the superior temporal gyrus.
- A lesion there can cause slight hearing impairment but not deafness, as hearing is bilaterally represented.
- The limbic system is located in the uncus & hippocampus in the medial and inferior surfaces of the temporal lobe.
- It handles smell (uncus), mood, and memory.
- A lesion there can cause uncinate fits with olfactory hallucinations, Temporal lobe epilepsy, and anterograde amnesia (loss of memory for recent events).
- The Auditory Associative Area(area 21,22), Wernicke's Area is adjacent to areas 4 and 42, and involves recognition and recall of sounds. Lesion in this region involves Auditory agnosia in which the patient hears, but does not recognize what he hears.
Occipital Lobe
- The visual sensory area (area 17) functions in the reception of visual images.
- The visual associative area (areas 18 and 19) is anterior to area 17.
- It functions as a center for reflex conjugate eye movement and the recognition and recall of images.
- Lesions in the visual area can cause visual agnosia, where the patient sees (a familiar face) but does not recognize what they see.
Parietal Lobe
- The cortical sensory area (areas 1, 2, and 3) is located in the post-central gyrus.
- The functions involve perception of cortical sensations from the opposite half of the body, like the motor area, with the body represented upside down.
- Lesions in the cortical sensory area can cause contralateral sensory loss.
- The angular gyrus (area 39) is located in the postero-inferior part of the parietal lobe.
- In the dominant hemisphere, it handles reading and recognizing visual symbols; lesion can lead to alexia.
- Supramarainal Gyrus(area 37) is on the dominant hemisphere, concerned with storage and recall of ideas of speech and ideas of complex voluntary motor areas. Lesion could cause Jargon's aphasia (word salad), or, or a praxia (inability to perform complex voluntary motor activity without paralysis or sensory loss).
Brain Stem
- The brain stem is formed of the midbrain, pons, and medulla.
- It connects the cerebral hemispheres to the cerebral peduncles, and the cerebellum by the superior, middle, and inferior cerebellar peduncles.
- It contains motor nuclei of cranial nerves.
Cerebellum
- The cerebellum lies behind the brainstem and occupies most of the posterior cranial fossa.
- It is concerned with the coordination of voluntary motor activities and maintenance of equilibrium.
Spinal Cord
- The spinal cord is an extension of the brain that runs through the spinal canal, ending at the lower border of the first lumbar vertebra.
- It is surrounded, nourished, and protected by the meninges, cerebrospinal fluid, fat, and a network of veins and arteries
- It consists of gray matter (cells) surrounded by white matter.
- It resembles the letter H (2 anterior and 2 posterior horns) in a transverse section.
- The spinal cord consists of 31 segments, there are 8 Cervical, 12 Dorsal, 5 Lumbar, and 5 Sacral Segments.
- Thirty-one pairs of nerve roots emerge from the spinal cord through spaces in each vertebra.
- The lowermost three segments of the spinal cord (S3, 4, 5) are known as the conus medullaris, while the segments above (L4, 5, S1, 2) are known as the epiconus.
- The cauda equina comprises a collection of lumbosacral nerve roots that fill the lower spinal canal below the L1 vertebra.
Corticospinal Tracts
- Upper motor neuron (UMN) cell bodies are located in the cerebral cortex.
- UMN axons decussate in the pyramids or at the level of exit of the lower motor neuron (LMN).
- Synapses of UMNs and LMNs occur in the anterior horn of the spinal cord.
- LMN axons exit via the anterior root.
Studying That Suits You
Use AI to generate personalized quizzes and flashcards to suit your learning preferences.
