CNS Flashcards
what will we be able to evaluate mental status through in the exam?
Cortex Basal ganglion Brain stem Cerebellum Cranial nerves
what are the 5 major categories in mental health exam?
Appearance Affect Language Thought Process/perception Cognitive function/Executive fx
what can change awareness? what are different descriptions of awareness?
- State of awareness of self and environment. Impaired by disease of the brainstem reticular activating system, or damage in parts of both hemispheres
Alert→ awake, not sleepy or tired, responding appropriately to environment
Lethargic→ (sleepy): awake, but tending to fall asleep if not gently stimulated
Stuporous → falling asleep unless vigorously stimulated
Comatose→ a sleep-like state from which the patient cannot be awakened
what should clinical exam of language include?
Spontaneous speech Naming Comprehension Repetition Reading Writing
aphasia
Disorder in producing or understanding language
aphasia may be the only sign of a new neurological disease, such as stroke, tumor or head trauma, or recent seizure
paraphasia
substituting similar sounding syllables or words
- “paraphasis errors”: pen for pencil or plentil for pencil
prosody
the melody or variable tone of speech
aphasia
disorder in understanding or producing language: spoken or written
- testing for aphasia: naming, comprehension, repetition and reading/writing
- due to localized lesion of dominant hemisphere (70% are left hemisphere dominant)
- can be caused by damage to either Broca’s or Wernicke’s area
dysphasia
impairment in USE of speech that is clear
i.e. failure to arrange properly in sentence
dysarthria
imperfect articulation due to lack of motor coordination; damaging event CNS or PNS, language comprehension and use may be fine.
Wernicke’s area
transforms sensory input –> neural word : giving words meaning
Broca’s area:
transforms neural word representations to spoken word
Broca’s aphasia
“expressive aphasia” - have understanding of spoken language, but can’t articulate
Wernicke’s aphasia:
have ability to produce “fluent speech” but it makes no sense
apraxia
inability to turn verbal request into motor performance
(often seen with aphasic patients)
patients have difficulty with complex yet familiar activities, such as dressing or taking a shower, writing with a pen or pencil, using a comb or toothbrush, mimicking an examiner
Orientation testing?
- PERSON (name): seldom lost unless the patient has aphasia or schizophrenia
- PLACE (location): often lost in some hospitalized patients, or delirious/extremely demented outpatients
- TIME: most commonly lost of these three; include time of day, day of week, month, year if possible
recent vs. remote memory
RECENT Memory: the ability to store new information, up to a few days
REMOTE Memory: more distant memories. Includes autobiographical (dates of graduation, marriage, etc.) or historical (date of wars, elections, sports, etc.)
Alzheimer’s dementia almost always begins as a progressive loss of memory; first recent, and then distant memory
how can insight be evaluated?
- explain a proverb
- explain a situational choice
- compare similarities/difference betwen objects
delerium
acute confusion episode, may be due to infection, uremia, alcohol withdrawal. Disoriented, poor judgment, delusions common, attention poor, mood fluctuates
“Everything’s an Emergency!”
- if they have poor attention, think delerium
Dementia
: insidious, slowly progressive, affect often flat, maintains orientation and attention until late in process. Altzheimer’s, B12 deficiency, hypothyroid, head trauma. Can have acute angry, delusional episodes later in the course of disease.
constructional ability
tests executive function
- ability to copy a figure or draw something simple
apraxia
inability to perform the command
what does cerebellum do?
receives sensory and motor input to coordinate motor activity, maintain equilibrium and control posture
rhomberg tests?
tests ataxia specific to posterior column function. While positioned and eyes open, balance is maintained. Closing eyes removes visual input and ataxia (falling over) occurs. Direction of the fall may indicate where the lesion is.
Cerebellar ataxia is present with eyes open or closed, ie, not a function of proprioceptive input.
Pronator drift
in same stance as for Romberg, if the arm pronates and drifts downward (and occasionally lateral) when eyes are closed it is specific for a contralateral corticospinal tract lesion/disease
dysmetria
movment that is clumsy, varied in speed/force, past the destination point
- can be tested with finger-to-nose eyes opened or with eyes closed
dysdiadochokinesis
one movement cannot be abruptly stopped and followed by the opposite movement: slow, irregular and clumsy
why is cranial nerve important?
Localizes pathologic processes specific to individual cranial nerves and can indicate where pathology is involved. This assists in diagnostic accuracy of neurologic disorders.
Headache: new onset or change in character Dysarthria Asymmetric facial features Dysphagia Hearing complaints Visual disturbance Ataxia/Asymmetric motor use
CN I
Olfactory is seldom tested, unless the patient complains of a loss of smell, or there is a frontal injury or possible frontal lobe tumor
Abnormalities seen with concussion(mild traumatic brain injury or TBI)
CN II/III testing
Acuity
Pupillary Reflex:Afferent is CN II, it senses the light.
Efferent: CN III (Oculomotor)
Visual field exam
Ophthalmoscopic (fundoscopic) examination is direct visualization of retina including optic disc and vessels. Optic nerve exam is primarily functional
CN III, IV, VI
Look at eyes in the primary position:
esotropia (medial deviation)
exotropia (lateral deviation)
Occulomotor:
Efferent pupillary response to light (III Oculomotor: levator palpebrae, sup/inf rectus, inf oblique, medial rectus) Extraocular movements: Six cardinal directions
Trochlear (IV Superior Oblique):
moves the eye downward and out.
Abducens (VI Lateral Rectus) move laterally
Remember the cover/uncover test to check bilateral central focus; looking for strabismus
Right fourth nerve palsy
Globe in right eye goes up and in, when it cannot go down and out (superior oblique)
Right Sixth nerve palsy
- cannot pull eye lateraly without lateral rectus innervation, results in on eye going in
horizontal diplopia
- Mild or total loss of lateral rectus function
- due to loss of CN VI
- often due to increased intracranial pressure b/c of its location in main sinus
how do you test the trigeminal nerve? corneal reflex?
Sensory: for the face, 3 divisions
Test sensation to each bilaterally: soft or temperature, and/or pinpick
Motor: masseter and pterygoid: clench teeth, move jaw side to side
Corneal Reflex: Gently touch lateral cornea w/ cotton or gauze
Afferent: CN V senses the stimulus
Efferent: CN VII motor to blink
Both eyes should blink together
central vs. peripheral effect of CN VII
central: cortex or brainstem: muscles of lower face only affected on one side
(lesion on opposite side)
peripheral: distal to brainstem, muscles of unilateral same side upper and lower face are affected. (lesion on same side)
Facial nerve?
Other things facial nerve does:
- Muscles of facial expression
- Upper face: closing the eyes, raising the eyebrows
- Lower face: smiling
- Taste of anterior 2/3 tongue
- Lacrimation
- Salivation
- Stapedius muscle of middle ear (dampens sound)
2 types of central lesions?
- Cerebral hemisphere lesion: signal must cross before it is manifested
- Lower facial weakness of the opposite side.
- Extremities on opposite side - Brainstem lesion:
- Lower facial weakness of the same side.
causes of peripheral lesion of CN VII?
Commonly compressed as it goes through the internal or external auditory canal by unknown, likely auto-immune processes (Bell’s palsy) or tumors, lacerations, infections (Lyme, etc.)
In a PERIPHERAL CN VII lesion, the entire seventh nerve is likely damaged, so there is weakness of the upper AND lower facial muscles on that same side
CN VIII
Vestibulocochlear
Hearing and Balance: The auditory portion of CN VIII is tested by the physician directly; most disorders of the vestibular portion are assumed from a history of positional vertigo
Hearing can be determined subjectively by how well the patient seems to understand the physician’s words, or by the examiner rubbing her index and thumb together one inch lateral to each ear of the patient, or the patient’s hair can be rubbed about one inch lateral to each ear
which nn. most commonly seen in TBI?
Injured in concussion (TBI): CN I, VII, VIII can be seen
CN IX and X testing?
gag reflex tests them both
CN IX is sensory to the soft palate, and CN X helps to raise the palate, so the Gag Reflex tests them both:
GAG REFLEX:
Afferent: CN IX
Efferent: CN X
Glossopharyngeal (IX) provides taste on the posterior 1/3 of tongue
CN XI testing?
Innervation of the sternocleidomastoid and trapezius muscles
Resist the patient shrug both shoulders simultaneously
Resist a head tilting to each side
CN XII testing?
Purely motor to only the tongue
Ask patient to stick out tongue (note if midline) and move side to side
Look also for atrophy or fasiculations of the tongue
In case of a CN XII peripheral lesion, the tongue deviates to the SAME SIDE
how can insight be evaluated?
- explain a proverb
- explain a situational choice
- compare similarities/difference betwen objects
delerium
acute confusion episode, may be due to infection, uremia, alcohol withdrawal. Disoriented, poor judgment, delusions common, attention poor, mood fluctuates
“Everything’s an Emergency!”
- if they have poor attention, think delerium
Dementia
: insidious, slowly progressive, affect often flat, maintains orientation and attention until late in process. Altzheimer’s, B12 deficiency, hypothyroid, head trauma. Can have acute angry, delusional episodes later in the course of disease.
constructional ability
tests executive function
- ability to copy a figure or draw something simple
apraxia
inability to perform the command
