Nervous system functions
What are the two major divisions of the nervous system?
CNS and PNS
Which lobe houses the primary motor cortex?
Frontal lobe
Which cranial nerve controls facial expression and lip movement?
Facial nerve (CN VII).
Which artery supplies Broca’s and Wernicke’s areas?
Middle Cerebral Artery (MCA).
What is the basic functional unit of the nervous system?
The neuron
The PNS carries sensory information to the CNS and motor commands ______ the CNS.
From
The primary visual cortex is located in the ________ lobe
Occipital
The cranial nerve essential for phonation (vocal fold movement) is CN ____.
X (Vagus)
The Circle of Willis is formed by the carotid arteries and the ______ arteries.
Vertebral
A reflex arc always begins with a _______ that detects a stimulus.
Receptor
A client cannot sense when food is in the left side of their mouth. Which major nervous system function is impaired?
Sensory input
Which cortical area is critical for speech comprehension?
Wernicke’s area
Match the nerve to the function:
Tongue movement →
Hypoglossal (CN XII)
A blockage in the left MCA can cause what communication deficit?
Aphasia (expressive, receptive, or global).
What ion rushes INTO the neuron during depolarization?
Sodium (Na⁺)
What does “integration” mean in the nervous system?
Processing and interpreting sensory input to determine an appropriate response.
A patient can speak fluently but makes nonsensical errors and doesn’t understand language. Which region is likely damaged?
Wernicke’s area in the left temporal lobe.
If CN V is impaired, what part of speech may be affected?
Jaw movement for articulation (opening/closing the mandible).
Why are watershed areas of the brain vulnerable during low blood pressure?
They lie between major arteries and receive the least direct blood supply.
A patient’s gag reflex is absent. Which two cranial nerves may be impaired?
CN IX (Glossopharyngeal) and CN X (Vagus)
Explain why all three nervous system functions (sensory → integration → motor) are required for producing intelligible speech.
Because we need sensory feedback to monitor speech, the brain to integrate the message, and motor output to move the articulators.
Why does left frontal lobe damage often impair speech production but not hearing?
Because speech is controlled by the left frontal lobe, while hearing is processed in the temporal lobe.
Explain why damage to CN X can affect both speech and swallowing.
Because CN X controls the larynx, velum, and pharynx
A stroke patient shows dysarthria on the right side of the face.
Which hemisphere’s blood supply was likely affected?
The left hemisphere
Why are reflex arcs important for protecting the body even before the brain fully processes the stimulus?
Because reflexes happen at the spinal cord level, allowing fast automatic responses.