Phys. Diagnosis / Neuro / (Mental Status and CN's)
Brain Anatomy / Occipital Lobe
Vision
Contents of Mental Status
-Appearance and Behavior -Speech and Language -Mood -Thoughts and Perceptions -Basic Cognitive Functions -Higher Cognitive Functions -Special Techniques
Cranial Nerves
12 pairs emerging from base of brain within the skull Motor, sensory, both or specialized functions Symptoms specific to area and function of nerve CN deficits can be due to nerve or brain lesions Cranial nerves emerge from mainly the brainstem (which is between the brain and cerebellum) Technically cranial nerves are part of the peripheral nervous system (not the CNS) even though they come out from the brainstem.
Common Abnormal CN Findings
Abnormal or Asymmetrical Pupils (II, III) Ptosis (III) Abnormal Eye Position (III, IV, VI) Facial Droop or Asymmetry (VII) Hoarse Voice (X) Articulation of Words (V, VII, X, XII)
Special CNS Tests
Asterixis Metabolic encephalopathy in patients with impaired cognitive function Ask patients to hold up hands like they are trying to stop traffic; wait for 1-2 mins for flapping motion that is asterixis Liver failure, respiratory failure, azotemia(increased nitrogen from renal dysfunction), drug toxicity, electrolyte dysfunction Meningeal signs Nuchal rigidity: Brudzinski's sign, Kernig's sign
CN Overview
CN I - smell CN II - visual acuity, visual fields, ocular fundi CN II, III - pupillary reactions CN III, IV, VI - EOM CN V - corneal reflex, facial sensation, jaw movements CN VII - facial movements CN VIII - hearing CN IX, X - swallowing, rise of palate, gag reflex CN V, VII, X, XII - voice and speech CN XI - shoulder and neck movements CN XII - tongue symmetry and position
Corneal Reflex
CN V(trigeminal) - Sensory ophthalmic branch for sensory reflex CN VII(facial) - Motor response to reflex Corneal reflex: touch cornea not conjunctiva with cotton and look for blinking. If blink, then sensory CN V (Trigeminal) is intact and motor response CN VII (Facial) is intact. Absence of blinking suggests lesion of CN V or VII. May not be intact in contact lens wearers.
CN VIII, Acoustic (Vestibulocochlear)
Cochlear branch:Hearing Screen hearing: finger rub or whisper (2 feet behind/ occlude contest ear w/ finger Test for Lateralization (Weber test) Compare Air and Bone Conduction (Rinne test) Vestibular branch: Balance (check for nystagmus) This is the nerve along which the sensory cells (the hair cells) of the inner ear transmit information to the brain. It consists of the cochlear nerve, carrying information about hearing, and the vestibular nerve, carrying information about balance. The vestibulocochlear nerve consists mostly of bipolar neurons and splits into two large divisions: the cochlear nerve and the vestibular nerve. The cochlear nerve travels away from the cochlea of the inner ear where it starts as the spiral ganglia. Processes from the organ of Corti conduct afferent transmission to the spiral ganglia. It is the inner hair cells of the organ of Corti that are responsible for activation of afferent receptors in response to pressure waves reaching the basilar membrane through the transduction of sound. The exact mechanism by which sound is transmitted by the neurons of the cochlear nerve is uncertain; the two competing theories are place theory and temporal theory. The vestibular nerve travels from the vestibular system of the inner ear. The vestibular ganglion houses the cell bodies of the bipolar neurons and extends processes to five sensory organs. Three of these are the cristae located in the ampullae of the semicircular canals. Hair cells of the cristae activate afferent receptors in response to rotational acceleration. The other two sensory organs supplied by the vestibular neurons are the maculae of the saccule and utricle. Hair cells of the maculae activate afferent receptors in response to linear acceleration.
Brainstem/Cerebellum
Deeper brain structures Brainstem (midbrain, pons, and medulla oblongata) Coordinates sides of body Controls breathing and heartbeat Controls consciousness and sleep cycle (reticular activating system) Cerebellum Coordinates voluntary movements Utilizes sensory data to control muscle tone, equilibrium and posture - Most primitive area of the brain
CN IV, Trochlear
Downward, inward movement of the eye SNOT - Superior oblique towards the nose - trochlear Innervates superior oblique muscle The trochlear nerve is unique among the cranial nerves in several respects. It is the smallest nerve in terms of the number of axons it contains. It has the greatest intracranial length. Other than the optic nerve (cranial nerve II), it is the only cranial nerve that decussates (crosses to the other side) before innervating its target. Finally, it is the only cranial nerve that exits from the dorsal aspect of the brainstem.
Thoughts and Perceptions
Evaluating for thought disorders: severe depression, schizophrenia, psychotic disorders, mania, OCD, etc. Patients with dementia or delirium may appear to have thought disorders 9% of patients have personality disorders with inflexible and pervasive behavior that deviates from expectations Perceptions or sensory awareness of your environment. Illusions are misinterpretations of real external stimuli IE rustling leaves sounds like voices vs hallucinations experiences but lack actual external stimuli Thought process is how people think. Tangential/derailment shifting topics, flight of ideas, Thought content is what people think. Obsessions intrusive thoughts/urges, compulsions acts in response to obsession, delusion - false fixed personal belief not amenable to change, Insight is awareness that symptoms are normal/abnormal Judgement is comparing and evaluating alternatives
Brain Anatomy/ Frontal Lobe
Frontal lobe Voluntary skeletal movements, motor speech (Broca's area), emotions, affect, awareness of self, problem solving. Frontal lobe - boss of the brain - muscle control and cognitive function- Broca's aphasia-"expressive aphasia" usually with right sided weakness - broken speech - fixed by singing Broca's area - can understand language but unable to produce words - partially fixed by singing - left hemisphere
Higher Cognitive Function
Information and Vocabulary (Intelligence) (asking about work, hobbies...) Calculating Ability Simple math Abstract Thinking Proverbs (ie. don't count your chickens before they hatch) Similarities (how are oranges and apples alike?) Constructional Ability Draw/copy a clock Draw shapes (intersecting pentagons)
CN III, Oculomotor
Innervates superior rectus, inferior rectus, medial rectus, inferior oblique, levator palpebrae superioris muscles. Remaining muscles are innervated by CN IV Does two things - motor muscle movement and parasympathetic fibers to ciliary ganglion to constrict the pupils Second innervation is to the ciliary muscles which control the shape of the eye and constrictor papillae muscle which constricts the pupil Fibers travelling in the oculomotor nerve and producing pupillary constriction seen in near reaction are part of the parasympathetic fibers that constrict the pupil and cause ciliary muscle contraction seen in accommodation(CN 2,3,4) and medial rectus muscle contraction seen in convergence Light reaction pathology: CN III palsy: Ptosis OS, downward and outward gaze
CN VI, Abducens
Lateral deviation of the eye ; Innervates lateral rectus muscle
Appearance and Behavior
Level of consciousness: lethargic(drowsy but will open and look at you before falling back asleep), obtunded(open and look at you but don't really respond), in a stupor Do you have to yell to arouse them? Do they respond appropriately and reasonably quick? Posture and motor behavior: Agitated, crying, anxiously fidgeting, pacing, involuntary movements? Hygiene: remember those who are being cared for by others - demented patients in SNF - are they clean? Manner and relationship to persons: paranoia, looking around suspiciously, flat affect, apathy of the demented(dulled affect with detachment and indifference), hallucinating or talking to people not there
CN IX, CN X
Listen to the patient's voice Hoarse or nasal? Ask patient to swallow Watch for symmetric rise of palate Gag reflex Watch for symmetric rise of palate
MMSE
Mini Mental State Examination Now a shorter version, easier to administer Limitations, falling out of favor Used to screen for cognitive dysfunction or dementia, to follow patients with dementia 30 points possible, <23 points suggests cognitive impairment
MoCA
Montreal Cognitive Assessment Designed as a rapid screening tool for milder cognitive impairment, takes about 10 min 30 points possible, <26 pts is abnormal Considered more sensitive and specific than MMSE
CN V, Trigeminal
Motor Temporal/masseter muscle (jaw clench) Lateral movement of the jaw (open and move jaw from side to side) Sensory (light touch, pain) 1. Ophthalmic 2. Maxillary 3. Mandibular(motor and sensory) The trigeminal nerve (the fifth cranial nerve, also called the fifth nerve, or simply CNV) is a nerve responsible for sensation in the face and certain motor functions such as biting and chewing. It is the largest of the cranial nerves. Its name ("trigeminal" = tri- or three, and -geminus or twin, or thrice twinned) derives from the fact that each trigeminal nerve, one on each side of the pons, has three major branches: the ophthalmic nerve (V1), the maxillary nerve (V2), and the mandibular nerve (V3). The ophthalmic and maxillary nerves are purely sensory. The mandibular nerve has both cutaneous and motor functions.
CN X, Vagus
Motor: Palate, Pharynx, Larynx Sensory: Pharynx, Larynx This means that the vagus nerve is responsible for such varied tasks as heart rate, gastrointestinal peristalsis, sweating, and quite a few muscle movements in the mouth, including speech (via the recurrent laryngeal nerve) and keeping the larynx open for breathing (via action of the posterior cricoarytenoid muscle, the only abductor of the vocal folds). It also has some afferent fibers that innervate the inner (canal) portion of the outer ear, via the Auricular branch (also known as Alderman's nerve) and part of the meninges. This explains why a person may cough when tickled on the ear (such as when trying to remove ear wax with a cotton swab).
CN XI, Spinal Accessory
Motor: Sternocleidomastoid and upper trapezius Look for atrophy or asymmetry of the trapezius muscles Ask patient to shrug shoulders against resistance Ask patient to turn their head against resistance; watch and palpate the sternomastoid muscle on the opposite side Joins with vagus nerve and shares some functions with the vagus nerve - often considered the cranial portion of the vagus nerve - hence called the spinal accessory nerve Traditional descriptions of the accessory nerve divide it into two parts: a spinal part and a cranial part. But because the cranial component rapidly joins the vagus nerve and serves the same function as other vagal nerve fibers, modern descriptions often consider the cranial component part of the vagus nerve and not part of the accessory nerve proper. Thus in contemporary discussions of the accessory nerve, the common practice is to dismiss the cranial part altogether, referring to the accessory nerve specifically as the spinal accessory nerve. The spinal accessory nerve provides motor innervation from the central nervous system to two muscles of the neck: the sternocleidomastoid muscle and the trapezius muscle. The sternocleidomastoid muscle tilts and rotates the head, while the trapezius muscle has several actions on the scapula, including shoulder elevation and adduction of the arm. Like other cranial nerves, the spinal accessory nerve begins in the central nervous system and exits the cranium through a specialized hole (or foramen). However, unlike all other cranial nerves, the spinal accessory nerve begins outside the skull rather than inside. In particular, in the majority of individuals, the fibers of the spinal accessory nerve originate solely in neurons situated in the upper spinal cord. These fibers coalesce to form spinal rootlets, roots, and finally the spinal accessory nerve itself, which enters the skull through the foramen magnum, the large opening at the base of the skull. The nerve courses along the inner wall of the skull towards the jugular foramen, through which it exits the skull with the glossopharyngeal (CN IX) and vagus nerves (CN X). Owing to its peculiar course, the spinal accessory nerve is notable for being the only cranial nerve to both enter and exit the skull.
CN IX, Glossopharyngeal
Motor: pharynx Sensory: posterior portions of tympanic membrane/ear canal, pharynx, posterior tongue including taste (salty, sweet, sour, bitter), parotid gland This is a difficult nerve to isolate in testing, and is combined in testing with CN X (vagus) There are a number of functions of the glossopharyngeal nerve: 1. It receives general sensory fibers (ventral trigeminothalamic tract) from the tonsils, the pharynx, the middle ear and the posterior 1/3 of the tongue. 2. It receives special sensory fibers (taste) from the posterior one-third of the tongue. 3. It receives visceral sensory fibers from the carotid bodies, carotid sinus. 4. It supplies parasympathetic fibers to the parotid gland via the otic ganglion. 5. It supplies motor fibers to stylopharyngeus muscle, the only motor component of this cranial nerve. 6. It contributes to the pharyngeal plexus. The glossopharyngeal nerve has five distinct general functions: 1. Branchial motor (special visceral efferent) - supplies the stylopharyngeus muscle. 2. Visceral motor (general visceral efferent) - provides parasympathetic innervation of the parotid gland. 3. Visceral sensory (general visceral afferent) - carries visceral sensory information from the carotid sinus and carotid body. 4. General sensory (general somatic afferent) - provides general sensory information from the skin of the external ear, internal surface of the tympanic membrane, upper pharynx, and the posterior one-third of the tongue. 5. Special sensory (special afferent) - provides taste sensation from the posterior one-third of the tongue.
CN XII, Hypoglossal
Motor: tongue Listen to the articulation of the patient's words Inspect the tongue at rest and with movement Ask patient to protrude tongue, move tongue from side to side Look for symmetry and position Test strength of the tongue the tongue will be curved away from the side of the cortical damage To test the function of the nerve, a patient is asked to stick their tongue straight out. If there is a loss of innervation to one side, the tongue will curve toward the affected side, due to unopposed action of the opposite genioglossus muscle. If this is the result of a lower motor neuron lesion, the tongue will be curved toward the damaged side, combined with the presence of fasciculations or atrophy. However, if the deficit is caused by an upper motor neuron lesion,, without the presence of fasciculations or atrophy. The strength of the tongue can be tested by asking the patient to poke the inside of their cheek while feeling the pressure on the outside of their cheek. Weakness of the tongue is displayed as a slurring of speech. The tongue may feel "thick", "heavy", or "clumsy." Lingual sounds (i.e., l's, t's, d's, n's, r's, etc.) are slurred and this is obvious in conversation. CN XII is called hypoglossal nerve because it is below the tongue. It controls tongue movements of speech, food manipulation, and swallowing.
CN VII, Facial
Observe for facial droop or asymmetry Motor: Ask Patient to do the following, note any lag, weakness, or asymmetry: Raise eyebrows Close both eyes tightly Smile / Show teeth Frown Puff out cheeks Test eye strength Sensory: taste(anterior 2/3) CN VII emerges from the brainstem between the pons and the medulla, and controls the muscles of facial expression, and functions in the conveyance of taste sensations from the anterior two-thirds of the tongue and oral cavity. It also supplies preganglionic parasympathetic fibers to several head and neck ganglia. Pathology: -Bell's palsy will affect the lacrimal & salivary glands and taste as well as facial muscles. (facial nerve lesion) (eyebrow goes down) -Supranuclear lesion would be a stroke most commonly. (lower side of face)
Cognitive Functions
Orientation Time, place, person Attention Digit span, serial 7's, spelling backward Remote Memory When is your birthday? Where were you born/raised? Recent Memory Who is the US President? What is the weather? New Learning Ability I'm going to tell you 3 objects. Repeat them after me and again in 2 mins when I ask you to.
Mental Status Check List
Orientation: ask name, date, location General wellbeing: ask mood, thoughts/perceptions Aphasia (speech & language): 1 stage command, repeat phrase, name common objects, read sentence, write sentence Cognitive function: repeat 3 objects immediately and in 2 mins; recent and remote memory Higher cognitive function: general info, calculation, abstract thinking Attention Point to your nose No ifs, ands or buts Birthday Presidents, dates of wars/events (be culturally sensitive) Serial 7's or simple math Interpret proverb or similarities Spell WORLD or PEACE backwards
Brain Anatomy / Parietal Lobe
Parietal lobe Data processing (math), interpretation of tactile data, comprehension of written words (reading, writing), recognition of body parts Parietal - sensation - touch, pain and pressure. Ex: Lesion of right parietal lobe may result in neglect of the left side of the body or inability to draw the left side of a picture
Basal Ganglia/ Diencephalon
Processing center, some automatic functions, more basic/primitive behavior - but they all have to be developed and controlled, not born with sophisticated control of these areas Diecephalon - thalamus and hypothalamus. Thalamus - router - sorting data Hypothalamus - circadian rhythm Basal ganglia - made up of nuclei - below cerebral cortex - motor control - parkinsons affects the basal ganglia Basal Ganglia Control of gross automatic movements (walking) Diencephalon - Thalamus Processes sensory information, relays signals to cerebral cortex Hypothalamus Maintains homeostasis, regulates temp, controls endocrine system Governs emotional behavior (sex drive, anger)
Speech and Language
Quantity: Talkative, expansive, nonfluent or have broken speech as in broca's aphasia Rate: accelerated speech of mania Articulation: dysarthria(defective articulation), aphasia is disorder of language. Evaluating patients for CNS lesions such as stroke, brain tumors; can also have disorganized speech due to disorganized thoughts with psychotic disorders Point to your nose - word comprehension No ifs ands or buts - repetition Expressive/nonfluent aphasia - preserved comprehension with slow nonfluent speech vs sensory/receptive aphasia like Wernicke with is impaired comprehension with fluent speech and they will have much of testing impaired vs brocas they will be fair with reading and word comprehension but not as good with naming/repetition or writing Aphasia - disorder of language, dysarthria: defective articulation
Depression Screening
SIG E CAPS can be helpful mnemonic: Sleep problems Interest (loss, including sex) Guilt Energy (lack) Concentration (lack) Appetite changes Psychomotor changes (restless or lethargic) Suicidal ideations
CN I, Olfactory
Sense of smell Check for patency Identify scent with eyes closed Check one side at a time, use different scents Each olfactory nerve has one odor receptor The specialized olfactory receptor neurons of the olfactory nerve are located in the olfactory mucosa of the upper parts of the nasal cavity. The olfactory nerves do not form two trunks as do the remaining cranial nerves. Rather, they consist of a collection of many sensory nerve fibers that extend from the olfactory epithelium to the olfactory bulb, passing through the many openings of the Cribriform plate of the Ethmoid bone, a sieve-like structure. Olfactory receptor neurons continue to be born throughout life and extend new axons to the olfactory bulb. Olfactory ensheathing glia wrap bundles of these axons and are thought to facilitate their passage into the central nervous system. The sense of smell (olfaction) arises from the stimulation of olfactory (or odorant) receptors by small molecules of different spatial, chemical, and electrical properties that pass over the nasal epithelium in the nasal cavity during inhalation. These interactions are transduced into electrical activity in the olfactory bulb, which then transmits the electrical activity to other parts of the olfactory system and the rest of the central nervous system via the olfactory tract. The olfactory nerve is the shortest of the twelve cranial nerves and only one of two cranial nerves (the other being the optic nerve) that do not join with the brainstem. Trigeminal nerve carries the pain receptors not the olfactory Isopropyl alcohol inhalation helps nausea
CN II, and CN III
Swinging flashlight test shown - Pupillary light reaction is both from CN II and CN III as the sensory pathways detecting the light are CN II and the motor pathways leading to pupillary constriction are CN III. Marcus gunn pupil or relative afferent pupillary defect is an issue with afferent or optic nerve portion
Brain Anatomy / Temporal Lobe
Temporal lobe Sensory speech (Wernicke's area), long-term memory(hippocampus), hearing Temporal - auditory/language/memory - Wernicke's aphasia- "sensory aphasia" - word salad - speak fluently but poor comprehension
CN III, IV, VI
Test Extraocular Movements (EOM) Check convergence and accommodation Identify nystagmus Nystagmus - rhythmic oscillation of the eyes typically suggesting a cerebellar, inner ear or drug toxicity - can also be congential - difficulty hold visual fixation or gaze. Think about when you are watching a train drive by Accommodation - pupil constriction and lens changes(can't see). Convergence - eyes going towards nose(IV)
CN II, Optic
Test Visual Acuity (snellen test) Screen Visual Fields by Confrontation (static finger wiggle test and kinetic red target test) Visualize optic fundi Also light reflex Fiber tracks of the mammalian central nervous system (as opposed to the peripheral nervous system) are incapable of regeneration, and, hence, optic nerve damage produces irreversible blindness. The fibers from the retina run along the optic nerve to nine primary visual nuclei in the brain, from which a major relay inputs into the primary visual cortex. The eye's blind spot is a result of the absence of photoreceptors in the area of the retina where the optic nerve leaves the eye.