Daily quizzes for exam 4

Which cognitive domain is relatively spared in the early stages of Alzheimer Disease?

Procedural memory Memory loss associated with AD dementia is regressive, starting with the most recent episodic memories and slowly wiping out memories from the distant past. In contrast, procedural memory is relatively preserved until later in the disease course. Language disturbance, especially word-finding difficulties, is a common early symptom but is generally mild. Executive dysfunction (as assessed by deterioration in the ability to execute previously familiar multistep activities such as cooking a meal, organizing a trip, or maintaining the household) is a hallmark of the disorder.

Long-term memories of places, things, and events (explicit or declarative memory) probably are "stored" as synaptic structural changes in neurons of the

cerebral neocortex, especially association areas. Consolidation is the process of storing new information in long-term memory. Novel factual information is relayed from the relevant sensory association areas to the hippocampal complex for encoding. Following a prolonged period of processing, the encoded information is relayed back to the same association areas and (with the exception of strongly autobiographical episodes) no longer depends on the hippocampal complex for retrieval.

Which one condition is definitely not associated with a possible progression to dementia?

Prosopagnosia Although Frontotemporal dementia, Alzheimer disease, Parkinson disease and Creutzfeldt-Jakob disease each have very different underlying pathophysiology, all are associated with possible progression to dementia. Prosopagnosia is a visual agnosia resulting in face blindness; it is not insidious but generally results from stroke and if the resulting infarct is isolated to the infratemporal/occipital regions is not linked to further cognitive decline.

Cyclooxygenase activity is necessary to synthesize:

Prostaglandins Arachidonic acid is converted by cyclo-oxygenases (COX-1 and COX-2) into prostaglandins and prostacyclins, that among other things sensitize a heterogeneous range of nociceptors and promote vasodilation; and thromboxanes, that trigger platelet aggregation and leukocyte modulation. Reducing the inflammatory reaction (eg by decreasing prostaglandins through inhibition of cyclooxygenases would be expected to reduce the nociceptive response.

Which tracts serve as the two principal hypothalamic pathways regulating the autonomic nervous system?

dorsal longitudinal fasciculus hypothalamospinal tract The principal hypothalamic output to autonomic brainstem nuclei (ie the parasympathetic nuclei such as the Edinger-Westphal nucleus and dorsal motor nucleus of the vagus) descends via the dorsal longitudinal fasciculus (DLF). The DLF also innervates the periaqueductal gray nuclei, and the monoaminergic nuclei such as the raphe nuclei and the locus ceruleus. Another tract, the hypothalamo-spinal tract, projects to the sympathetic neurons of the lateral horn of the spinal cord, and the parasympathetic neurons in the sacral spinal cord. Damage to this hypothalamospinal tract (eg in lateral medullary syndrome or cord hemisection) is one cause of Horner's syndrome.

Define general anesthesia.

An altered physiologic state characterized by loss of consciousness analgesia of the entire body, amnesia, and to some degree muscle relaxation There is no universally accepted definition of general anesthesia. However, general anesthesia should encompass at least: An altered physiologic state characterized by loss of consciousness; analgesia of the entire body, amnesia, and to some degree, muscle relaxation.

The hypothalamus and the thalamus collectively are part of the ___________ and are separated by the ___________.

diencephalon, hypothalamic sulcus

You are working the sidelines as a team physician at a high school soccer game. One of the players jumps up for a header and collides with the elbow of another player. She falls to the ground and does not immediately get up. You rush onto the field to evaluate her. She is lying on the ground and appears to be passed out. She opens her eyes when you call her name. She begins to move her extremities and brings her hand to her forehead in apparent pain. She can squeeze your hand on command. You ask her some orientation questions, but she can't remember where she is or what has happened. What is her GCS (Glasgow Coma Scale) score?

13 The Glascow Coma Scale is used to classify the severity of a TBI. It measures verbal and motor responses as well as eye opening. She opens eyes to voice (3), follows motor commands (6) and is disoriented when talking to you (4). Total GCS = 13. Eye opening Scoring: 1 None 2 To pain 3 To voice 4 Spontaneous Motor Scoring: 1 None 2 Extensor posturing 3 Flexor posturing 4 Withdraws to pain 5 Localizes to pain 6 Normal Verbal scoring: 1 None 2 No words, only sounds 3 Words, but not coherent 4 Disoriented conversation 5 Normal conversation (CDC TBI report)

A patient with a history of paroxysmal hemicrania has been reading about cluster headache on the internet and asks if that is what he has. You begin educating the patient on cluster headache. According to the International Classification of Headache Disorders - II (ICHD-II) criteria, the duration of a cluster headache is:

15 - 180 minutes The duration of a cluster headache is 15 to 180 minutes. The International Classification of Headache Disorders-II (ICHD-II) criteria for cluster headache require at least five attacks fulfilling the following: severe or very severe unilateral orbital, supraorbital, and/or temporal pain lasting 15 to 180 minutes if untreated. The headache must be associated with at least one of the following: ipsilateral conjunctival injection and/or lacrimation, ipsilateral nasal congestion and/or rhinorrhea, ipsilateral eyelid edema, ipsilateral forehead and facial sweating, ipsilateral miosis and/or ptosis, a sense of restlessness, or agitation. Attacks occur at a frequency of 1 every other day to 8 per day, and symptoms are not attributable to another disorder. hours to days = range of duration of migraine headache 30 minutes to hours to days = range of duration of tension-type headache

You have a vial of 8 ml of 2% solution of lidocaine. How much lidocaine is present in 1 mL of solution?

20 mg 1% is 1g in 100 ml or 10 mg in 1 ml, 2% would be twice that, ie 20 mg/ml

Refer to the neuroradiology images, and match each to its most likely diagnosis

A - Ependymoma B - Vestibular schwannoma C - Meningioma D - Glioblastoma

Fibromyalgia is caused by:

Abnormal pain modulation in descending inhibitory pathways FMS is a "disorder of central pain processing", such that a mildly painful stimulus like firm pressure on a muscle that when in "normal" patients would be experienced as a 2-3/10 intensity, is described instead at a 6-10/10 intensity. Many so-called "functional pain" conditions are likely all or in part CNS pain processing disorders, so called "functional" because end-organ "structural" disease is not found to be pathologically abnormal. FMS falls into the category of "Central Sensitization Syndromes" or CSS. These are arguably not "neuropathic pain", but this spectrum involves a "neurogenic" mechanism, one that amplifies non-noxious sensation into a "hyperalgesic" state of abnormal pain sensitivity. Abnormal descending pain modulation is believed to be part of the pathophysiology.

Which mechanism best describes opioid cellular action of reduced excitability of neurons and blockade of neurotransmitters following G-protein catalytic conversion?

Adenylate cyclase inhibition and reduction of calcium conductance and increase in potassium conduction. Mu, delta, or kappa receptor activation each results in the catalytic conversion of the pertussis toxin sensitive G-proteins (Gi/o) from the GDP bound form to the GTP bound form. G•GTP inhibits adenylate cyclase, and Gregulates the conductance of calcium and potassium channels in the neuronal membrane. Calcium conductance is reduced and potassium conductance is increased. Both effects reduce the excitability of neurons and block neurotransmitter release.

The triptan medications are effective in treatment of migraine because they work at which of the following subreceptors?

Agonism at 5HT-1B,5HT-1D The triptans work as agonists at the serotonin receptor subtypes 5HT-1B and 5HT-1D. Agonism at 5-HT1-B receptors constricts the pain-producing intracranial, extracerebral blood vessels in the meninges. Agonism at 5-HT1D receptors presynaptically inhibits trigeminal peptide release and interferes with central trigeminal nucleus caudalis (TNC) nociceptive transduction and processing, whereas those of the nucleus tractus solitarius in the brain stem are thought to inhibit nausea/vomiting. Ultimately, these effects result in reversal of vasodilation, decrease in neurogenic inflammation, reduction of central nociceptive signal transmission to the thalamus and cortex, and cessation of activity in other ascending pathways to the cortex, which result in a decrease in the associated migrainous symptoms, such as photophobia and phonophobia.

While amyloid (Aβ) plaques remain one of the defining pathophysiological features of Alzheimer Disease, what evidence suggests that the etiology of Alzheimer is far more complex?

Alzheimer patients can have Aβ deposits and not show signs of dementia The pathogenesis of AD involves more than just the presence of Aβ plaques. The figure below shows a diagram revealing complex interactions between amyloid levels and many downstream pathological features that all contribute to neuronal loss in AD (referred to as the amyloid cascade hypothesis). A true diagnosis of AD (including early-onset, familial forms) requires the presence of Aβ plaques, however, the inverse is not true: individuals can have evidence of high levels of the Aβ protein but not show clinical signs of dementia.

Which of the following best characterizes a patient's experience of pain?

An unpleasant perception with both a sensory and emotional component, in response to either actual or anticipated tissue damage. Nociception is not pain. Pain is BOTH a sensory (biologic) AND an emotional (psychologic and sociologic) experience. Pain can be an alarm of danger and/or a sign of damage. As such, pain alerts the individual of threatening internal and external environmental dangers, and performs the critical life function of signaling need for bodily damage protection. The "pain alarm" may sound in response to actual danger or may activate in anticipation of danger. Even if damage cannot be demonstrated with physical exam, lab tests or imaging studies, pain is a "real" experience even when tissue injury has not evidently occurred; "malingering" (faking pain purposively with a clear goal of receiving a reward) is a rare occurrence in common clinical practice and if considered requires a formal diagnostic evaluation. Pain remains defined multi-dimensionally as a bio-psychosocial experience: "Pain is an unpleasant sensory and emotional experience associated with actual or potential tissue damage, or described in terms of such damage.

The regulation of internal body temperature including adjustments made during an infection (fever) are due to an antagonistic interaction between which two regions of the hypothalamus?

Anterior and posterior zones The relative concentrations of warm-sensitive preoptic anterior area (POA) neurons that promote heat loss, and cold-sensitive posterior hypothalamus neurons that promote heat generation, has resulted in the POA often being termed the heat dissipation center and the posterior hypothalamus being labeled the heat generation/conservation center. The hypothalamic thermoregulatory system functions to induce fever. Recall from Invaders & Defenders that infection results in dendritic cells and macrophages releasing prostaglandin E2 (PGE2) as well as other pyrogenic cytokines. PGE2 is the ultimate mediator of an increased temperature set point. PGE2 acts on neurons in the POA, specifically reducing excitability and discharge rates of warm sensitive neurons. This yields two specific effects. First it allows cold sensitive neurons within the posterior hypothalamic nucleus to engage the DMH, the PVN, and the raphe nucleus (RN) in the medulla. Fever signals sent to the DMH and RN lead to stimulation of sympathetic output, which evokes non-shivering thermogenesis activities such as tachycardia, brown adipose tissue thermogenesis, and skin vasoconstriction to decrease heat loss from the body surface. Second, it raises the set-point value required to engage heat dissipation mechanisms. That is, PGE2 through a secondary messenger system increases the temperature needed to engage warm sensitive neurons. The use of antipyretics such as aspirin and NSAID counteracts fever by interrupting the synthesis of PGE2.

Which of the following best describes principal uses of opioids?

Antidiarrheal, antitussive, anxiolytic, analgesia. Principal uses are for: control of moderate to severe pain, cough, and diarrhea. More specifically, therapeutic uses of opioids are for 1. Severe visceral pain — A 10 mg dose of morphine relieves moderate post operative pain in 90% of patients, and severe pain in 70%. 2. Preoperative preparation — decreases anxiety; decreases the dose required for other anesthetics. 3. Post operative pain — decreases pain and anxiety. 4. General anesthesia — I.V. large doses. 5. Cough — antitussive (codeine is effective; note that the non-scheduled opiate derivative dextromethorphan has largely replaced opiates for this use). 6. Diarrhea — morphine decreases intestinal motility. 7. Terminal illness — sedation and anxiolytic effects. Contraindications for opioids are: head injury, respiratory depression, acute asthma, seizures, biliary tract spasm, prior history of drug abuse.

Opioids are:

Any drug which demonstrates agonist and/or antagonist activity at the mu, delta and kappa types of opioid receptors Many opioids are "synthetically" manufactured, such as oxycodone, fentanyl, and methadone. In legal terminology, "narcotics" refers to any drug that is specifically "prohibited," such as heroin, LSD, cocaine, and, in some states, marijuana. It is most clear (and less pejorative) to use the term "opioids" if referring to drugs that pharmacodynamically interact with the mu, kappa, or delta opioid receptors. "Opiates": Derivatives of natural derived opium with "full µ-agonist effect": codeine, morphine, hydrocodone, hydromorphone "Synthetic opioids": These interact with the µ -receptor with less structural resemblance but "full µ-agonist effect" : oxycodone, methadone, fentanyl "Mixed opioids": These are µ-agonists, but bind weakly with the µ receptor and additive analgesic effects due in large part to monoamine re-uptake inhibition (much like antidepressants): tramadol, tapentadol. "Partial opioid agonists": Bind to but only incompletely activate the µ receptor: buprenorphine "Opioid antagonists" Bind and block µ-receptor activity: naloxone, naltrexone

A 41-year old patient presents with what you suspect to be tension-type headache. Which one of the following symptoms is included in the International Classification of Headache Disorders - II (ICHD-II) criteria for this disorder?

Bilateral vise-like squeezing pain Tension-type headaches are infrequent episodes of headache lasting minutes to days. The pain is typically bilateral, pressing or tightening in quality (non-pulsating) and of mild to moderate intensity, and it does not worsen with routine physical activity. There is no nausea or vomiting, but mild photophobia or phonophobia may be present. Vomiting, nausea, throbbing/pulsating pain and aggravated pain with routine physical activity are features of migraine headache.

Which of the following is not a common focal neurologic sign of brain injury?

Head drop Focal neurologic signs of brain injury include post-traumatic seizures, anosmia/hyposmia, cranial nerve deficits, visual field cuts, aphasia, gait/balance problems, tinnitus, and photosensitivity. (Syllabus reading)

You are working the sidelines as a team physician at a high school soccer game. One of the players jumps up for a header and collides with the elbow of another player. She falls to the ground and does not immediately get up. You rush onto the field to evaluate her. All of the following signs/symptoms indicate she may have sustained a TBI except:

Headache TBI is defined as a disruption in the normal function of the brain. An alteration in brain function is suspected if any one of the following signs is present: 1. Any period of loss of or decreased consciousness 2. Any loss of memory for events immediately before (retrograde amnesia) or after the injury (post-traumatic amnesia) 3. Neurologic deficits such as muscle weakness, loss of balance and coordination, disruption of vision, change in speech and language, or sensory loss 4. Any alteration in mental state at the time of injury such as confusion, disorientation, slowed thinking, or difficulty with concentration Headaches can occur separately from a brain injury and are therefore not indicative of disruption of brain function. (CDC TBI report)

Impaired function of the descending inhibitory pain modulation system plays a key role in which of the following?

Central sensitization pain syndromes such as seen in fibromyalgia pain. Central sensitization of pain is the increased responsiveness of nociceptive neurons in the CNS to their normal or subthreshold afferent input. The descending inhibitory pathways inhibit pain, hence are "ant-algesic," by a complex process of down modulation of peripheral nociceptive input into the CNS. The principal neurotransmitters in the "descending inhibitory" system are the same monoamines used in the treatment of depression and anxiety, namely norepinephrine, serotonin, and dopamine. Descending modulation of pain is a key concept across the field of pain research and clinical practice and helps to explain why pain hurts more or less depending on the situation/context.

Which of the following best corresponds to treatment goals for palliative pain care?

Improve quality of life and relieve suffering for patients with advanced illness. Palliative pain care, or pain care associated with end-of-life conditions, is a circumstance where unintended consequences of treatment are acceptable (e.g., death results from potential complications of pain treatments, such as excessive respiratory suppression). Quality of remaining life then prevails, and function is no longer a primary goal. Palliative pain care is frequently needed in times of inexorably progressive pain of terminal cancer, as called for in "hospice care". Goal of palliative pain treatment: Comfort and dignity at the end of life.

2 weeks after a 25 yo sprained her ankle while trail running, was medically evaluated, and fully compliant with advised non-weight bearing and splinting/immobilization, she now presents with 10/10 pain and excess sweating in her injured leg. Physical exam findings include: normal temperature, pulse and BP; antalgic gait; affected lower leg is swollen, and skin over ankle and foot is red and shiny. You note tactile and mechanical allodynia, cool skin, and hyperhidrosis. Her diagnosis is which of the following?

Complex regional pain syndrome CRPS (previously referred to as "reflex sympathetic dystrophy (RSD)" or "causalgia"), is a severe pain disorder occasionally caused by direct nerve injury, but most often after a quite minor distal extremity trauma without any evident nerve trauma, sometimes even following a prolonged interval of immobilization, such as occurs when splinted or casted. Similar to phantom limb pain, the experience of pain in patients with CRPS is thought to result from abnormal brain mapping, a disorder of the body scheme and resulting loss of positional representation (and at times even "ownership") of the individual's personal body space, consequent to a change in the way the brain constructs a spatial representation of the affected limb. Touch and/or minimal movement is extremely painful ("tactile" or "mechanical" allodynia). Patients may experience sensory and/or motor "neglect" and astereognosis (inability to identify objects by touch) of an affected extremity, clinically resembling that seen with parietal lobe CVA, though without the cell death seen following a stroke. Clinical appearance resembles acute inflammation: swollen extremity, with fluctuating red, blue or white discoloration of the skin. Sometimes unilateral sweating can be so severe you will see it dripping off the affected limb. Over time skin becomes shiny and hairless. Though all pathology looks to be in the visibly affected limb, the disorder is a central pain syndrome. In some respects, phantom pain is like CRPS: the patient's brain is producing the pain- not the hand or foot that is no longer present. The "peripheral" physical exam findings are a result of "neurogenic neuroinflammation, which is the response to efferent not afferent release of neuropeptides by C-fibers into adjacent non-neural structures (e.g. skin, vascular, and lymphatic.) In CRPS, the brain is literally "referring" central pain into the periphery, with the CNS triggering the peripheral inflammatory response that you can see in your patients' hands or feet.

Which of the following is the most common initial life-threatening consequence of local anesthetic overdose?

Convulsive seizure Seizures are the most common life threatening consequence of a local anesthetic overdose. This is true for amide and ester type local anesthetics. Although ventricular fibrillation can occur this is uncommon and likely only to occur with bupivacaine overdose.

A 7-year-old boy is brought in by his mother because his school teacher says that he has moments of lack of attention. His EEG shows 3 Hz generalized spike and slow wave bursts seen as interictal findings suggestive of absence seizures. The best first-line treatment for him is:

Ethosuximide Ethosuximide blocks T-type voltage-gated sodium channels, and is used for the treatment of absence seizure and generalized seizure.

Which statement about the speed of onset of nerve blockade with local anesthetics is correct?

Faster in myelinated fibers In general, smaller fibers are blocked more easily than larger fibers, and myelinated fibers are blocked more easily than unmyelinated fibers. Activated pain fibers fire rapidly; thus, pain sensation appears selectively blocked by local anesthetics. Peripheral fibers in a thick nerve bundle are blocked sooner than those in the core because they are exposed earlier to higher concentrations of the anesthetic.

Match the drug

Generalized Absence Seizures; Blocks T-type voltage-gated Ca channels - Ethosuximide Na+ channel blocker, Partial Epilepsy and generalized epilepsy. Use for bipolar depression. Safety issue: rash/Steven Johnson syndrome - Lamotrigine Na+ channel blocker, Use for partial seizure; use as mood stabilizer. Rash/Steven-Johnson syndrome and hyponatremia are potential adverse effects - Carbamazepine Blocks Na+ and Ca++ channels. Better for Generalized Epilepsy; and use as a mood stabilizer; use for migraine associated w neural tube defects - Valproic acid Increases GABA activity, Risk for DT's if abrupt withdrawal; use for status epilepticus; use for anxiety - lorazepam Increases GABA activity, often used to control seizures in Pediatric Population - phenobarbitol

A 52-year-old man has had headaches and difficulty concentrating for the past 2 months. He then begins to exhibit odd behavior, including shooting his rifle in his back yard, which the neighbors find disconcerting. He then suffers a grand mal seizure, and is admitted to the hospital. MRI of the brain reveals a large mass with extensive necrosis in the left cerebral hemisphere extending across corpus callosum into the right hemisphere. Which of the following neoplasms is he most likely to have?

Glioblastoma He most likely has a glioblastoma, the highest grade glioma and the most malignant of all primary brain tumors, with rapid and extensive growth. Gliomas in adults usually arise above the tentorium. Meningiomas are slow-growing and usually well-circumscribed tumors located over the surface of the brain. Medulloblastomas are typically tumors of childhood located below the tentorium in the cerebellar vermis, though like high-grade gliomas, they may seed along the neuraxis. Metastases may be multiple or solitary, but are usually not extensive enough to cross the midline. Pilocytic astrocytomas are typically seen in children and arise in the posterior fossa, often in a cerebellar hemisphere.

Epilepsy is defined as:

Having two or more unprovoked seizures separated by more than 24 hours Epilepsy is defined as having two or more unprovoked seizures separated by more than 24 hours. Seizures are defined as paroxysms of abnormally hyperexcitable and hypersynchronous cortical activity, which results in a change in sensation, behavior or sensorium. Spread of clonic movements through contiguous body parts unilaterally is the definition of Jacksonian March. Automatism refers to coordinated, repetitive motor activity often resembling voluntary movement during impaired cognition.

Mr. Jones is a 54 year old gentleman with localization-related (partial) epilepsy who has continued to have seizures despite moderately high doses of carbamazepine. You are considering adding a second drug but would like to use one that has a different mechanism of action. Which of the following drugs has a different mechanism?

Levetiracetam Levetiracetam (which binds to SV2A presynaptic protein and decreases synaptic release) is the only drug listed here that does not share the similar mechanism of action as the others listed. Carbamazepine, Phenytoin, and Lamotrigine all block Sodium Channels.

Which of the following anesthesia drugs does not act on the GABA A receptor?

Ketamine As CNS depressants, anesthesia drugs usually increase the threshold for firing of CNS neurons by affecting ion channels by interactions with membrane lipids or proteins, with subsequent effects on neurotransmission. Inhaled anesthetics (eg. isoflurane, sevoflurane), barbiturates (eg. sodium thiopental, phenobarbital), benzodiazepines (eg. lorazepam, diazepam, midazolam), etomidate, and propofol facilitate γ-aminobutyric acid (GABA)-mediated inhibition at GABA-A receptors. Ketamine does not produce its effects via facilitation of GABA-A receptor functions, but possibly via its antagonism of the action of the excitatory neurotransmitter glutamic acid on the N-methyl-D-aspartate (NMDA) receptor.

Methadone, a long-acting orally active analgesic prescribed for both chronic pain and addiction, is a

Long-acting strong opioid agonist. Methadone (strong agonist, high efficacy) is an orally active, long acting opioid useful in the treatment of opioid addiction. Abstinence syndrome (withdrawal) takes longer to develop with methadone.

Pain assessment requires measurement of all of the following, except:

Magnitude of injury or deformity seen on imaging Imaging (e.g. MRIs and X-rays) can be very useful in diagnosing structural damage or disease, but does not inform us about whether or not such structural changes will cause "pain". For instance, age related changes on radiologic images are common, such as osteoarthritis, arthritis or intervertebral disc changes, but often do not correspond to the pain experienced by a patient. Many painful conditions demonstrate no abnormalities at all using standard imaging techniques.

Which of the following best corresponds to treatment goals for chronic pain care?

Management of nondrug and drug treatments to optimize physical and psychologic function. Chronic pain persists for more than 3 months, typically beyond the ordinary time for tissue injury to heal. Recurrent episodes of acute pain are not considered chronic pain when intervals of time pass between pain occurrences. When chronic inflammatory conditions (such as Crohn's disease or rheumatoid arthritis) remain "active", or when other persistent states of active nociception (such as severe osteoarthritis) are present, overlapping episodes of what is called: "acute-on-chronic pain" may occur. Acute pain can also occur in patients who have been already experiencing chronic pain, e.g. when new injury or disease develops, or when surgery is indicated for a new or revision surgical procedure. Some patients report periodic exacerbations of chronic pain as "acute pain flairs", however this should be considered and so managed as poorly controlled chronic pain. Goal of chronic pain treatment: Improve function and quality of life.

When discussing inhalational anesthetics what does MAC stand for?

Minimum alveolar concentration. MAC - minimal alveolar concentration- is defined as the alveolar concentration of an anesthetic that is required to prevent a response to a standardized painful stimulus in 50% of patients.

Which inhalational agent has the least effect on blood pressure?

Nitrous oxide Nitrous oxide is the least potent of the above and has the least effect on the blood pressure. Effects of inhaled anesthetics: CNS Inhaled anesthetics decrease brain metabolic rate, reduce vascular resistance and thus increase cerebral blood flow. High concentrations of enflurane may cause spike-and-wave activity and muscle twitching, but this effect is unique to this drug. Although nitrous oxide has low anesthetic potency (i.e., a high MAC), it exerts marked analgesic and amnestic actions. Cardiovascular Most inhaled anesthetics decrease arterial blood pressure moderately. Enflurane and halothane are myocardial depressants that decrease cardiac output. Nitrous oxide is less likely to lower blood pressure than are other inhaled anesthetics. Respiratory Although rate of respiration may be increased, all inhaled anesthetics cause dose-dependent decrease in tidal volume and minute ventilation, leading to an increase in arterial CO2 tension. Inhaled anesthetics decrease ventilatory response to hypoxia even at subanesthetic concentrations (e.g., during recovery). Nitrous oxide has the smallest effect on respiration.

Sensory input transmitted via C-fiber and A-delta afferents activated by noxious stimuli best describes which type of pain?

Nociceptive pain Nociceptive pain: Pain that arises from actual or threatened damage to non-neural tissue and is due to the activation of nociceptors. Neuropathic pain: Pain caused by a lesion or disease of the somatosensory nervous system. Can be either "central" or "peripherally" mediated. Hyperalgesia: Increased pain intensity from a stimulus that "normally" provokes pain. Augmented pain response to an otherwise normal threshold Sensitization can occur at the level of the peripheral nociceptor (cell body locates in the dorsal root ganglion) or within the central nervous system (dorsal horn, medulla, cerebral and cortical neuroplasticity). Peripheral: Increased responsiveness and reduced threshold of nociceptive neurons in the periphery to the stimulation of their receptive fields. Central: Increased responsiveness of nociceptive neurons in the central nervous system to their normal or subthreshold afferent input.

You are admitting a 28 year old patient who sustained a severe TBI from a motorcycle accident to the acute inpatient rehabilitation unit. They have significant impairments in balance, cognition (attention, executive thinking, memory), speech (expressive aphasia) and behavior (mood swings, aggression). All of the following are appropriate goals for each member of the rehab team to focus on except:

Occupational therapy to counsel him on getting back to work Occupational therapists focus on training patients to perform activities of daily living (dressing, bathing, toileting, grooming). They can also provide targeted therapies for deficits in strength or coordination in the upper extremity. Vocational counselors discuss planning for return to work. They can help facilitate transitions back to a former occupation or find a new job within the abilities of the patient. Physical therapists focus on mobility training which includes balance, gait, endurance and lower extremity strengthening. Rehabilitation psychologists are important members of the brain injury team because they can assist with coping with disability, behavioral therapy and treating mood disorders. (TBI Infocomics)

Which of the following correctly describes the difference between an "extended release (ER)" as compared to an "immediate release (IR)" opioid?

Opioids that have been pharmacologically designed to prolong the mechanism of drug release are called extended release (ER) opioid formulations. "Extended release" is a pharmacokinetic term that describes a drug with a short "half life" that is manufactured in a variety of ways to become time-released, and so due to its slower release into the body permits a steadier and longer lasting effect level than it would otherwise have. "Long-acting" opioids have intrinsically prolonged half lives, so they do not require an "extended-release" mechanism to acheive a sustained effect. ER opioids are not required for those patients requiring chronic use of opioids.

Which diagnostic test can assess the presence of cortical Aβ load?

PET imaging PET imaging technology can visualize in vivo most molecules with various binding potentials as long as they can be tagged with a radioactive isotope (review the neuroradiology session from Week 2). A compound has been engineered that binds to the amyloid protein (called Pittsburgh compound B (PiB); it is a radioactive analog of thioflavin T. PiB when coupled to PET scans can quantify cortical amyloid burden. Serum testing cannot visualize cortical amyloid levels and MRI and CT scans can only reveal structural related impairments.

Assessment of chronic pain is best measured by obtaining patient self-reports of:

Pain interference with enjoyment of life, functioning, sleep, and mood. A variety of "patient self-reported outcome (PRO)" tools are recommended for measuring pain. The most commonly known measure used in clinical and research settings gauges pain intensity and is helpful in focusing attention on under-treatment of acute pain. However, for chronic pain, use of the numerical scale can be very misleading. A number of evidence-based tools are available to initially assess and then follow patients with chronic pain multi-dimensionally. An essential element of chronic pain assessment is evaluation by self-report of the severity of "pain interference" with patients' enjoyment of life (eg PEG tool), general function, sleep and mood. Using measurement tools to assess and track chronic pain enables you to track your patients' progress effectively.

The autonomic features of lacrimation, rhinorrhea and nasal congestion seen in the trigeminal autonomic cephalalgias are due to the activation of which nucleus?

Parasympathetic outflow from the superior salivatory nucleus Lacrimation, rhinorrhea and nasal congestion arise from activation of the parasympathetic system. Parasympathetic outflow from the superior salivatory nucleus of cranial nerve VII leads to activation of lacrimal and nasal mucosal glands. Parasympathetic fibers travel with the greater superficial petrosal nerve of cranial nerve VII to the sphenopalatine ganglion, synapse, and then travel with the maxillary division of cranial nerve V to the lacrimal glands. There is a brainstem connection between the trigeminal nucleus caudalis and the superior salivatory nucleus causing the trigeminal-autonomic reflex. This reflex is activated by a noxious stimulus applied to the trigeminal distribution for example, getting hit in the face with a ball will cause lacrimation and rhinorrhea.

Which medication can cause a life-threatening rash?

Phenytoin

A 7-year-old boy is brought in by his mother because his school teacher says that he has moments of lack of attention. His EEG shows 3 Hz generalized spike and slow wave bursts seen as interictal findings suggestive of absence seizures. The treatment that may worsen his condition is:

Phenytoin Phenytoin adverse effects are nystagmus, ataxia, sedation, impaired concentration

Irritable bowel syndrome and chronic pelvic pain are both associated with:

Post-traumatic stress disorder (PTSD) and Fibromyalgia

Properties of local anesthetics do not include which of the following?

Preferential binding to resting channels Local anesthetics bind preferentially to sodium channels in the open and inactivated states. Resting channels have a lower affinity for local anesthetics.

Which of the following best corresponds to treatment goals for acute pain care?

Relieve pain to degree sufficient to facilitate an expected recovery. Acute pain is characterized by recent onset, most often the result of an injury, or after a surgery (e.g. post-operative). Acute pain persists for less than 3 months, generally the time needed for disease, injury, or a threat to the body to resolve or heal. Goal of acute pain treatment: Reduce pain intensity

Evidence based recommendations for non-drug treatments for pain include which of the following?

Sleep hygiene and cognitive behavioral therapy

Jelnic has experienced seizures after a motorcycle accident in which he sustained a closed head injury. He recalled noticing a funny rising sensation in his stomach before he lost consciousness. His partner described that he initially appeared confused but subsequently stiffened his whole body followed by repetitive whole body shaking. The etiology of the patient's seizures is best described as:

Structural

Which drug is most likely to cause hyperkalemia leading to cardiac arrest in patients with spinal cord injury or muscular dystrophy?

Succinylcholine Succinylcholine is a depolarizing neuromuscular-blocking agent, which produces sustained opening of the nicotinic cholinergic receptor channel. Under normal conditions, post-junctional membrane depolarization results in leakage of potassium that produces an increase of 0.5 - 1.0 mEq/L in serum K+ concentration. When succinylcholine depolarizes muscle that has been traumatized (crush injury) or denervated (upper motor neuron lesion) enough K+ may leak from cells to produce systemic hyperkalemia and cardiac arrest. This susceptibility to hyperkalemia is thought to be caused by proliferation of junctional and extrajunctional cholinergic receptors. The patient population at risk for succinylcholine-induced hyperkalemia includes patients with upper motor neuron lesions resulting from stroke, brain or spinal cord injury among others.

During an office visit, a 46-year old man with a long-standing history of recurrent headaches is diagnosed for the first time with migraine. He has a history of anxiety, hypertension, hyperlipidemia, tobacco abuse, and is noncompliant with medications. Family history is significant for his mother having migraine and his father dying from a "heart attack" in his mid-fifties. If this patient presented to the emergency department at the very onset of a migraine, what treatment should be avoided?

Sumatriptan Triptans are optimal for abortive treatment of migraine in the absence of cardiovascular contraindications. Thus, sumatriptan is contraindicated in patients with known coronary heart disease and should only be used after a cardiac workup if a patient has multiple cardiac risk factors. This patient has several cardiovascular risk factors, such as uncontrolled hypertension, hyperlipidemia, tobacco abuse, gender, age, and a family history of early heart disease. This patient would require a full cardiac evaluation (including a stress test), prior to any use of triptans, and they would still be used only cautiously with the first dose administered in the office if his risk factors were controlled and cardiac evaluation showed no evidence of cardiac ischemia. NSAIDS would be appropriate treatment choices.

The 28 yr old patient referred to in the previous question has completed inpatient rehabilitation program after three weeks. The patient is now able to walk around the unit without any assistive devices or hands-on assistance, but still cannot remember which room is theirs. The patient's speech is improved and they can communicate basic wants and needs. Which of the following pieces of advice will you give the family?

The patient should wear an ID bracelet in case he gets lost. The patient clearly still has memory impairments and therefore should not be managing their own medications or driving. A diagnosis of severe brain injury does not mean that the patient will never re-integrate back into society, though it may take a long time and a lot of hard work to get there. (TBI Infocomics)

A 22-year old mildly overweight woman presents to the emergency department with increasing frequency of previously diagnosed migraines. The attacks are occurring 4 days per week and are lasting the entire day. Other medical history is unremarkable with the exception of mild asthma and recurrent constipation. What would be the best preventive medication to start in this patient?

Topiramate There are two parts to this question Identify prophylactic (preventive) and acute treatment Identify side effects and contraindications Sumatriptan is an acute treatment for migraine, not a preventive therapy. From this list the only preventive treatments are: Amitriptyline (tri-cyclic anti-depressant) Propranolol (beta-blocker) Topiramate (anti-convulsant that affects sodium channels) Verapamil (calcium channel blocker) Amitriptyline is not the best option for this patient since the patient is overweight and amitriptyline can cause weight gain of 20 to 30 lbs, obesity is one of the modifiable risk factors of migraine progression and we encourage patients to achieve their optimal body weight. Propranolol can exacerbate asthma. Verapamil is not FDA indicated as preventive medication for migraine, even though some clinicians use it for migraine prevention. It is a good preventive medication for treatment of cluster headache. Verapamil can cause constipation, and this patient already has constipation. Topiramate is FDA indicated treatment of migraine headaches. As a bonus it can cause weight loss, a highly desirable attribute of topiramate. The main side effects are paresthesias, weight loss and cognitive problems. It is contraindicated in patients with kidney stones and acute angle glaucoma.

An overweight 41-year old woman with hypertension, recurrent kidney stones, and increasing migraine frequency wishes to begin a preventive medication to control her migraines. Which of the following would be a poor choice?

Topiramate Topiramate (an anti-convulsant) is often used in overweight migraine patients because it can be associated with weight loss, but given that this patient has a history of recurrent kidney stones, topiramate becomes a poor choice. All of the other choices have been shown to be beneficial for preventive purposes and are commonly used. Because she is hypertensive, a β-blocker or calcium-channel blocker (like verapamil) would be a good treatment option. Preventive therapy should always be targeted not only for headache prevention, but also for any comorbidities that are present.

Which of the following listed category analgesics is a first-line therapy for chronically painful diabetic neuropathy?

Tricyclic antidepressant (TCA) Selection of an antidepressant drug for pain is mostly dependent on whether it increases synaptic levels of norepinephrine, much more so than its increase in serotonin. Clinical trials show "tricyclic antidepressants" (TCAs) and "serotonin/norepinephrine re-uptake inhibitors" (SNRIs), but not "serotonin reuptake inhibitors" (SRIs), effective for a variety of neuropathic pain conditions. Most robust evidence supports effectiveness for post-herpetic neuralgia (number needed to treat [NNT]), 2.7, diabetic peripheral neuropathy (NNT, 1.2-1.5), atypical facial pain (NNT, 2.8-3.4), and central pain (NNT, 1.7).

Which of the following headache types is not currently considered a trigeminal autonomic cephalalgia by the International Classification of Headache Disorders-II (ICHD-II) criteria?

Trigeminal neuralgia Trigeminal neuralgia is not associated with autonomic features and is therefore not classified as a trigeminal autonomic cephalalgia. It is currently classified in the International Classification of Headache Disorders-II (ICHD-II) criteria as one of the "cranial neuralgias, facial pain and other headaches." The headaches that are classified as one of the "cluster headache and other trigeminal autonomic cephalalgias" include cluster headache, paroxysmal hemicrania (PH), short-lasting unilateral neuralgiform headache with conjunctival injection and tearing (SUNCT), and probable trigeminal autonomic cephalalgia.

A 30-year-old woman with epilepsy from a head trauma at age 20 comes to your office because she is ready to start a family. Which medication should she definitely avoid?

Valproate Valproate blocks sodium and calcium channels, but is a teratogen and should be avoided in the treatment of seizures in child-bearing women.

Painful crisis in patients with Sickle Cell Disease is most commonly associated with which of the following?

Vaso-occlusive events in spleen, lung, and bone Sickle cell disease, which affects 1 in 600 African Americans, is associated with frequent and expectedly severely painful events caused by splenic, lung, and bone infarcts due to vaso-occlusion. Ischemic death of bone and visceral tissue is extremely painful, generating a cascade of hyper-nociception, and so treatment for pain is the primary cause of healthcare utilization for patients with sickle cell disease. Many patients with sickle cell disease require frequent emergency department care and hospitalizations since most events last up to a week, and 20% of patients experience such episodes monthly.

A 70-year-old man with a history of alcohol abuse following the death of his spouse 5 years ago has exhibited memory problems for the past 7 months, and he is noted by his immediate family to confabulate. He dies as a consequence of a hepatocellular carcinoma. At autopsy, his brain demonstrates bilaterally small mamillary bodies that show brown discoloration. Microscopically, there is gliosis, vascular proliferation and hemosiderin deposition in the mammillary bodies and periaqueductal gray matter. Which of the following is the most likely diagnosis?

Wernicke-Korsakoff syndrome Wernicke encephalopathy and Korsakoff syndrome are different conditions that often co-occur. Both are due to brain damage caused by a lack of vitamin B1, which is common in people who have alcohol use disorderLinks to an external site.. It is also common with conditions that result in malabsorption of nutrients, eg. with chronic illness or after weight-loss (bariatric) surgery. The symptoms and signs of Wernicke-Korsakoff syndrome reflect dysfunction of brain regions that have high demand for thiamine. These areas include the blood-brain barrier, anterior and centromedian thalamus, mammillary bodies, periaqueductal gray matter, superior and inferior colliculi, and floor of the fourth ventricle. Symptoms of Wernicke encephalopathy (due to damage to thalamus and hypothalamus) include: Confusion and loss of mental activity that can progress to coma and death Loss of muscle coordination (ataxia) Nystagmus, double vision, ptosis Alcohol withdrawal Korsakoff syndrome, or Korsakoff psychosis, tends to develop as Wernicke symptoms abate. Symptoms of Korsakoff syndrome: Inability to form new memories Loss of memory and confabulation (making up stories) Hallucinations Korsakoff syndrome becomes apparent in up to 80% of patients who survive Wernicke encephalopathy. It is characterized by disproportionate retrograde and anterograde episodic amnesia, transient confabulation, and hallucinations. The primary pathologic findings occur in the limbic system, especially the mamillary bodies, amygdala, and dorsomedial and anterior thalamus.

When is a basic drug ionized (most local anesthetics are basic drugs)?

When the pH is less than the PKA When a basic drug is in an acidic environment it is more ionized than non-ionized. When pH= pKa it is half ionized and half non-ionized. The commonly used local anesthetics are weak bases with at least one ionizable amine that can become charged through the gain of a proton. The degree of ionization is a function of the pKa of the drug and the pH of the medium. Because the pH of tissue may differ from the physiologic 7.4 (e.g., it may be as low as 6.4 in infected tissue), the degree of ionization of the drug will vary. Because the pKa of most local anesthetics is between 8.0 and 9.0 (benzocaine is an exception), variations in pH associated with infection can have significant effects on the proportion of ionized to nonionized drug. In infected (acidic) tissue there are many more protons available, this limits the ability of the local anesthetic to cross the lipid membrane and thus limits its effect.

Electrical stimulation of the amygdala in humans typically causes

anxiety and fear. Amygdalar stimulation in humans can cause a variety of emotions, but the most common is fear, accompanied by all its autonomic manifestations (e.g., dilation of the pupils, release of adrenaline, increased heart rate). Conversely, bilateral destruction of the amygdala (for example in Urbach-Wiethe disease) causes a great decrease in aggression and fear, and in animals, tameness and placidity.

The 'limbic lobe' of cortex is taken to include the

cingulate gyrus. Limbic lobe is a "geographic" term - it refers to the ring of cortex at the medial edge of the cerebral hemisphere, and includes the cingulate and parahippocampal gyri and the uncus. It thus includes parts of the frontal, parietal and temporal lobes.

The largest source of input from cortical sensory association areas to the hippocampal formation is via the

entorhinal cortex The entorhinal cortex is in the anterior part of the parahippocampal gyrus. In the broadest terms the entorhinal cortex receives a constant stream of cognitive and sensory information from the association areas of the neocortex, transmits it to the hippocampal formation for consolidation, retrieves it in consolidated form, and returns it to the association areas where it is encoded in the form of memory traces.

A 5yr old girl is brought to the pediatrician by her mother, who explains the daughter has complained of headache and has become progressively more lethargic over the past several weeks. MRI reveals a tumor within the fourth ventricle. The tumor is surgically removed and frozen sections reveal the presence of perivascular pseudorosettes. Which of the following is the most likely diagnosis?

ependymoma Ependymomas are seen in children, often in the 4th ventricle, and are histologically characterized by the presence of perivascular pseudorosettes. The other choices are more often found in adults, and involve glial cells.

Chad is a 17 year old teenager who plays baseball for his high school team. On a road trip to the playoffs he doesn't sleep well and the morning of his first game he has a seizure. When questioned, he doesn't recall any unusual sensations prior to losing consciousness. Observers said that his whole body stiffened for a few seconds and then he began to have repetitive whole body jerking lasting another 45 seconds. Upon awakening he was sore but had no neurologic deficits. This is an example of:

generalized tonic clonic seizure This is an example of generalized tonic-clonic seizure: Generalized because the person had a complete loss of consciousness. Tonic-clonic because this is exactly what he displayed--periods of tonic (body-stiffening) followed by clonic (rhythmic jerking) movements.

The 56 yr old person who died with this lesion had complained of severe headaches for several weeks, and friends had noticed personality changes. Based on the two photographs, the best diagnosis is

glioblastoma multiforme The photographs show a "butterfly lesion" in the post mortem brain specimen, vascular cell proliferation and pseudopallisading necrosis in the histopathology preparations, all 3 of which point to glioblastoma multiforme.

The anticonvulsants that are used to treat neuropathic pain are thought to pharmacodynamically act to :

inhibit evoked neuronal activity via voltage gated sodium and calcium channel blockade. Anticonvulsant (ACD) drugs are "adjuvant analgesics", and are often used as first-line therapy for neuropathic pain. Like antidepressants, they are neither opioids nor anti-inflammatories, targeting mostly central neural transmission pathways. They can be divided in two broad groups: the "calcium channel" modulators and the "sodium channel blockers". The ACDs with (variable) evidence for use in pain act on: Voltage Gated Sodium Channels (VGSC): Carbamazepine, Oxcarbazepine, Lamotrigine, Topiramate Voltage Gated Calcium Channels (VGCC): Gabapentin, Pregabalin, Levetiracetam

The paraventricular nucleus of the hypothalamus is a multi-tasker nucleus! Which of the following is true about the PVN nucleus? Mark all that apply.

it releases ADH (antidiuretic hormone, vasopressin) and oxytocin into the circulation in the posterior pituitary gland has direct influence over both sympathetic and parasympathetic outflow Paraventricular nucleus (PVN) is the master regulator of the ANS. PVN contains neurons that project via DLF onto preganglionic autonomic neurons in dorsal motor nucleus of vagus and other autonomic relay nuclei of the brainstem and via the hypothalamospinal tract onto preganglionic neurons in the lateral horn of spinal cord. PVN also contains magnocellular neurons that (together with those in the supraoptic nucleus) release vasopressin and oxytocin into the posterior pituitary, and parvocellular neurons that regulate the endocrine cells of the anterior pituitary.

Which of the following hypothalamic nuclei receives synaptic input from the hippocampus via the fornix, projects to the anterior nucleus of the thalamus, and plays a role in the consolidation of new declarative memories?

mammillary The mammillary body projects to the anterior nucleus of the thalamus, which projects in turn to the cingulate cortex, completing the Papez circuit from the cingulate cortex to the hippocampus with return to the cingulate cortex via the fornix, mammillary body, and anterior thalamic nucleus. This circuit plays a major role in consolidation of new declarative memories. Other forms of memory (eg procedural memory) are processed elsewhere (eg cerebellum and basal ganglia)

The primary hypothalamic site of pathology generally responsible for the memory problems associated with Wernicke-Korsakoff syndrome (the "triad" is confusion, ataxia, ophthalmoplegia, but memory loss and confabulation due to thiamine B1 deficiency are also part of the syndrome) is

mammillary bodies Wernicke-Korsakoff syndrome is most closely associated with short-term memory loss (i.e. anterograde memory impairment) with confabulation (invention of episodic events), due to disruption of communication between the hippocampus, the thalamus and the mammillary bodies. Note: although lesions elsewhere (including periventricular area of the hypothalamus, cortical and sub-cortical sites) can lead to Wernicke-Korsakoff syndrome, lesions in the mammillary body are the hallmark of the condition. Patients can also present with severely impaired conversation upon exam and significant confusion, ataxia, nystagmus and ophthalmoplegia (horizontal gaze palsy).

Anterograde amnesia (inability to form new memories) is often a result of damage to the

medial temporal lobes, bilaterally. The medial temporal lobe houses the entorhinal cortex, the hippocampus and the amygdala. It is convenient to lump these together in some cases. Damage to the hippocampus is associated with impairments in consolidation of new declarative memories.

A 4-year-old boy with ataxia and stumbling gait of a few months duration developed nausea, vomiting and headache. Imaging reveals a solid space-occupying mass in the posterior fossa midline. Which of the following is the most likely diagnosis?

medulloblastoma With this description, the most likely diagnosis would be medulloblastoma or ependymoma. Surgical removal and pathological examination would be needed to differentiate between these diagnoses, but the best choice from the options in the question as presented is medulloblastoma.

A bilateral lesion within the hypothalamus proper will generally manifest in some form of _________ impairment.

neuroendocrine Typically, unilateral lesions may not be noticeable or may cause only minimal impairment (remember that the hypothalamic connections are ipsilateral). Bilateral lesions produce more focal, circumscribed deficits, usually resulting in neuroendocrine disturbances, autonomic dysfunction, and/or limbic imbalance. Tumors or other insults to the hypothalamus and/or pituitary tend to lead to under- or overproduction of circulating hormones and produce disorders of growth (dwarfism, gigantism and acromegaly), sexual function (hypogonadism), body water control (diabetes insipidus), eating (obesity and bulimia) and adrenal cortical control (Cushing's disease and adrenal insufficiency). Tumors can also exert pressure on adjacent structures (mass effect). For example, recall that pituitary tumors (adenomas) can press on the optic chiasm, resulting in bitemporal hemianopia.

A 34 year old individual receives Midazolam during a colonoscopy procedure. Which of the following characteristics is not associated with benzodiazepines?

pain relief Properties of benzodiazepines do not include pain relief. They bind to GABA receptors and may indirectly treat pain due to relief of anxiety or sedation.

A 10-year-old boy started to be more clumsy than usual and had trouble keeping his balance when he was running on rough ground or up and down stairs. These symptoms became worse over a 10 month period, and he occasionally fell to the right. Exam showed dysmetria in the right upper and lower extremities. MRI showed a cystic lesion in the right cerebellar hemisphere. Which of the following is the most likely diagnosis?

pilocytic astrocytoma Pilocytic astrocytoma typically occurs in older children in a cerebellar hemisphere, resulting in coordination deficits on the ipsilateral side. This is a cystic lesion, usually with a mural nodule of tumor adjacent to a cyst. Glioblastoma typically occurs in adults in the cerebral hemispheres. Ependymoma occurs in children, but originates in the fourth ventricle, and would be a solid midline lesion. Medulloblastoma typically occurs in younger children, and is a solid lesion in the posterior fossa.

In the image, which structure is c?

pituitary stalk/infundibulum The pituitary stalk or infundibulum is the connection between the brain and pituitary. It contains the axons of supraoptic and paraventricular neurons which extend into the posterior hypothalamus and release oxytocin and ADH (vasopressin) into the venous system there. The hypothalamo-hypophyseal portal system is also located in the infundibulum: releasing and inhibiting factors from various hypothalamic nuclei are transported by this vascular route to endocrine cells in the anterior pituitary. A dramatic disorder of the hypothalamus is diabetes insipidus, resulting from interruption of the hypothalamic-hypophyseal pathway, most commonly from tumors' mass effect but also from head injury (a fracture at the base of the skull), aneurysms in the circle of Willis, and increased intracranial pressure. a=mammillary body b=anterior commissure d=optic chiasm e=lamina terminalis (anterior boundary of third ventricle) f=fornix g=interthalamic adhesion h=thalamus i= thalamus; just inferior to the arrowhead is the hypothalamic sulcus j=tectum of midbrain

A 28-year-old patient diagnosed with HIV developed neurological symptoms, including right hemiparesis, behavioral changes, and difficulty with word finding, over a period of months. MRI showed multiple lesions throughout the cerebral hemispheres. Which of the following is the most likely diagnosis?

primary CNS lymphoma With this description and a young adult with HIV, primary CNS lymphoma is the most likely diagnosis. It is more common in immunocompromised patients, and typically presents as a diffuse lesion or in multiple locations. Pituitary adenoma would present with hormonal abnormalities and bitemporal hemianopia (due to compression of the optic chiasm). Intracranial schwannoma is an extra-axial tumor that usually occurs on CNVIII, presenting with hearing and vestibular symptoms. Glioblastoma multiforme occurs in the cerebral hemispheres, but appears as a single lesion often extending across the midline, and typically not in a patient this young (although glioblastoma cannot be ruled out based on the patient's age).

What is the general function of melatonin?

serves as an indirect marker of environmental light levels

A 33-year-old woman with chronic headaches presents for evaluation. She states that she has had the headaches since she was 15 years old and that the headaches have become more frequent in the last two years. She says the headaches begin with visual phenomena and lead to severe, throbbing headaches over the left eye. Based on this history, when you ask what her preference is when she has the headaches and has no medication available, you are expecting her to say

she prefers wanting to rest/sleep in a quiet, dark room Her history suggests migraine, and wanting to rest in a quiet dark room is a classic response. People with cluster headaches typically prefer to move around when they are suffering from the headache.

Stress-evoked increase in HPA axis activity results in up-regulation of cortisol released by the adrenal cortex. In the acute stage of the stress response, cortisol does which of the following?

stimulates gluconeogenesis Cortisol mediates "alarm" reactions to stress. It stimulates hepatic gluconeogenesis and reduces energy expenditure from low-priority activities (such as the immune system function) sparing available glucose for the brain in order to survive immediate threat. It also enhances our ability to generate lasting memories of short-term events (referred to as flash-bulb memories).

A 25 year old male arrives at the ER and reports he was bench pressing 200 lbs when he had sudden onset of headache. This was very acute and severe in onset. He says he has never had a headache like this before. During the physical examination, he begins vomiting, and becomes lethargic and unable to answer questions, and subsequently loses consciousness.This presentation is consistent with

subarachnoid hemorrhage first and worst headaches are red flags--don't miss them!

Match each term with its appropriate description:

tonic movement - Sustained muscle contractions clonic movements - Repetitive brief muscle jerks (~2-3 times per second) tonic-clonic - Contraction followed by repetitive brief muscle jerks atonic - Sudden loss of muscle tone

A 27-year-old man begins to experience infrequent episodes of nausea, warmth rising through his body, and an unusual odor like rotting fish. His partner notices that afterward he may develop twitching of the left side of his face and an inability to speak for several minutes. Afterwards, the man appears dazed and cannot remember what has occurred. He has otherwise been well. Magnetic resonance imaging (MRI) of his brain is most likely to show a lesion in which area of the brain?

uncus The uncus is part of the medial temporal lobe within which the amygdala is located. Peri-amygdaloid cortex processes olfactory stimuli, and uncinate seizures are characterized by olfactory auras, with patients complaining of smelling foul odors. These auras can be accompanied by other types of auras such as rising epigastric discomfort and a sensation of fear.

A 58-year-old man presents with tinnitus and loss of hearing in the right ear, unsteadiness and dizziness. Symptoms were first noted 9 months prior to examination and progressed very slowly. His MRI is shown below. Which of the following diagnoses is most likely?

vestibular schwannoma This is a typical presentation in an adult of a vestibular schwannoma (also called at the cerebello-pontine angle. Deficits result from compression of CN VIII. This image shows the tumor extending into the internal auditory meatus, creating the "ice-cream cone sign" Glioblastoma typically occurs within the cerebral hemispheres. Ependymoma usually occurs in children, and arises in the fourth ventricle. Medulloblastoma usually occurs in children in the cerebellum. Primary CNS lymphoma typically occurs at multiple sites in immuno-compromised individuals.

In experimental animals, removal of the temporal lobes back to the level of primary auditory cortex results in Kluver-Bucy syndrome, which includes

visual agnosia, so they seem not to recognize objects and examine the same one repeatedly. In Kluver-Bucy syndrome The animals are fearless and placid. They do not respond to threats, to social gestures by other animals, or to objects they would normally flee from or attack. Male animals become hypersexual and are indiscriminate in their choice of mate. They show an inordinate degree of attention to all sensory stimuli, as though ceaselessly curious.They exhibit hyperorality, mouthing and eating inappropriate objects, as well as food in larger amounts than normal animals. Although they incessantly examine all objects in sight, these animals apparently recognize nothing and may pick up the same object over and over. This is called visual agnosia. Placidity and hypersexuality result from destruction of the amygdala, and the visual agnosia from damage to visual association areas on the inferior surface of the temporal lobe. The composite syndrome is tremendously detrimental. Human patients with bilateral temporal lobe damage display similar deficits.