Lesson 9, 10 & 11 Student Resource

Lesson 9 to 10 Lesson 9, 10 & 11 Student Resource Q: What symptoms did Mr. Tan present with after his fall? A: Slurred speech and difficulty swallowing, bilateral weakness in all four limbs, numbness below the neck, gait instability, involuntary eye movements1. Q: What did MRI and CT imaging reveal for Mr. Tan? A: MRI indicated spinal cord compression and possible brainstem involvement. CT imaging revealed cervical vertebral fractures (C4–C5)1. Q: Which brainstem structures could account for slurred speech and swallowing issues? A: The brainstem structures that provide the main motor and sensory innervation to the face and neck via cranial nerves (CN III–XII), especially the medulla oblongata1. Q: Which functions are typically lost in cervical spinal cord injuries? A: Bilateral weakness in all four limbs, numbness below the neck, gait instability, and loss of motor and sensory function below the level of injury1. Q: What imaging findings are consistent with brainstem compression? A: MRI shows spinal cord compression and possible brainstem involvement; CT shows cervical vertebral fractures1. Q: How do vertebral fractures affect the integrity of the spinal cord? A: Vertebral fractures can cause compression or damage to the spinal cord, leading to neurological deficits1. Q: Why does Mr. Tan have weakness in all his limbs? A: Cervical spinal cord injury interrupts motor and sensory pathways to both upper and lower limbs1. Q: Why is the brainstem like the trunk of a tree? A: The brainstem connects the cerebrum (branches and leaves) to the spinal cord (roots), acting as the trunk that supports and connects all parts1. Q: What might happen to the 'tree' if the trunk (brainstem) gets damaged? A: Damage to the brainstem can affect vital functions and disconnect the brain from the body, impacting the whole system1. Q: Can you think of some conditions where brainstem damage affected the whole 'tree'? A: Conditions like stroke, trauma, or tumors in the brainstem can affect the entire nervous system1. Q: What is the brainstem? A: The brainstem is the lower part of the brain, acting like a stalk, adjoining and structurally continuous with the spinal cord1. Q: What connects the cerebrum to the spinal cord and cerebellum, and is composed of the midbrain, pons, and medulla oblongata? A: The brainstem1. Q: What vital functions is the brainstem responsible for? A: Breathing, consciousness, blood pressure, heart rate, and sleep1. Q: What are the basic functions of the brainstem? A: Conducts all information between body and brain/cerebellum, origin of cranial nerves III–XII, conjugate eye movements, controls consciousness and sleep, cardiovascular and respiratory centers, cough/gag/swallow/vomit centers, sense of body balance, and motor control1. Q: Why don’t you stay asleep every time someone talks in a soft voice — but you suddenly wake up when your name is called across the room? A: The reticular activating system (RAS) in the brainstem helps decide which sounds or signals are important enough to wake up your brain1. Q: What part of your brainstem helps decide which sounds or signals are important enough to wake up your brain? A: The reticular activating system (RAS)1. Q: What is the reticular activating system (RAS)? A: The RAS is a network of neurons in the brainstem that works with the thalamus to manage wakefulness, awareness, and sleep cycles1. Q: What does the thalamus do in relation to the RAS? A: Routes the sensory signal to the right part of the brain1. Q: How do the RAS and thalamus work together? A: They help you notice important things and stay focused or wake up when needed1. Q: How many cranial nerves originate from the brainstem and which ones? A: 10 out of 12 cranial nerves (III–XII)1. Q: What are cranial nerve nuclei? A: Clusters of nerve cell bodies (gray matter) within the brainstem associated with specific cranial nerves1. Q: What does the brainstem act like for nerve signals? A: A highway for nerve signals traveling between the brain and the body1. Q: What are the two types of tracts in the brainstem? A: Motor (movement-related) and sensory (feeling-related)1. Q: If your brain wants to move your hand, or feel a gentle touch on your toe — how does that message travel through your body? A: Through ascending (sensory) and descending (motor) pathways in the brainstem1. Q: What is the role of 'ascending' and 'descending' pathways in the brainstem? A: Ascending pathways carry sensory information to the brain; descending pathways carry motor commands from the brain to the body1. Q: I’m the brain’s bouncer — tough and round, I guard the boss without a sound. Your brainstem’s tucked in nice and tight — through my hole it sees the light. What am I? A: The foramen magnum1. Q: What structure supports the face and protects the brain? A: The skull1. Q: What are the two subdivisions of the skull? A: Facial bones and the cranium (cranial vault)1. Q: What does the rounded cranium do? A: Surrounds and protects the brain and houses the middle and inner ear structures1. Q: What is the base of the skull called and what is its function? A: The cranial floor; it is connected to the brainstem and spinal cord via the foramen magnum1. Q: What is the foramen magnum? A: A large opening at the base of the skull that allows the brainstem to pass through and connect to the vertebral column1. Q: What happens when the brainstem is damaged? A: Loss of vital functions, possible paralysis, and disruption of signals between brain and body1. Q: What are "crossed" signs in brainstem lesions and why do they occur? A: Symptoms appear on opposite sides of the body due to crossing of nerve fibers in the brainstem1. Q: What is the vertebral column and what does it do? A: The vertebral column (spine) is a bony structure extending from the skull to the pelvis, supporting the head and torso, protecting the spinal cord, and allowing movement1. Q: How many vertebrae make up the vertebral column? A: 33 vertebrae1. Q: Fill in the blanks: There are 7 ________ vertebrae in the neck region, 12 ________ vertebrae in the mid-back, 5 ________ vertebrae in the lower back, the sacrum is formed by the fusion of 5 ________ vertebrae, and the 4 ________ vertebrae fuse to form the coccyx. A: cervical; thoracic; lumbar; sacral; coccygeal1. Q: What sits between each vertebra to provide cushioning and flexibility? A: Intervertebral discs1. Q: What are the main parts of a typical vertebra? A: Vertebral body, spinous process, transverse processes, vertebral foramen1. Q: What is the function of the vertebral foramen? A: Forms the spinal canal for the spinal cord1. Q: What is the spinal cord and what does it do? A: The spinal cord is a long, thin, tubular bundle of nervous tissue and support cells that extends from the medulla oblongata of the brain to the lumbar region, carrying signals between the brain and the rest of the body1. Q: How many pairs of spinal nerves branch from the human spinal cord? A: Thirty-one pairs1. Q: What is the difference between the posterior and anterior roots of spinal nerves? A: Posterior root is sensory (afferent), anterior root is motor (efferent)1. Q: What do dorsal and ventral rami do? A: Dorsal ramus supplies the back; ventral ramus supplies the front and limbs and forms nerve plexuses1. Q: What are dermatomes? A: Specific skin regions innervated by a spinal nerve1. Q: What are myotomes? A: Muscle groups innervated by specific spinal nerves1. Q: What are ascending and descending tracts in the spinal cord? A: Ascending tracts carry sensory information from the body to the brain; descending tracts transmit motor commands from the brain to the body1. Q: What can damage to spinal cord tracts cause? A: Sensory loss, muscle weakness, or paralysis below the injury1. Q: What is the objective of the Clinical Case Puzzle – What’s the Level? A: Understand the functional implications of spinal cord lesions at various levels, integrate knowledge of spinal cord anatomy with clinical reasoning, and enhance teamwork and discussion skills1. Q: What is the common question for all clinical case studies? A: Based on the sensory and motor findings, which spinal nerve root is most likely affected?1.