Test questions

What are meningiomas tumors?

encased in meninges Encapsulated, growing within their own membranes, usually benign, surgically removable

Partial Seizures Complex

often restricted to the temporal lobes Patient engages in compulsive and repetitive simple behaviors (automatisms)

Seasonal rhythms are under the control of the cells located within the ______.

pineal gland

anterior cerebral artery

supplies the medial portions of the frontal and parietal lobes and corpus callosum. The middle cerebral artery supplies large portions of the frontal, parietal, and temporal lobe surfaces. Branches of the anterior and middle cerebral arteries (lenticulostriate arteries) supply the basal ganglia and anterior limb of the internal capsule.

Posterior Circulation Ischemia

Posterior Cerebral Artery deficits can also involve memory and vision function Vertebrobasilar strokes confined to the brainstem will affect movement, sensation and consciousness but could also compromise cognition

Seizure Disorders/Epilepsy

Primary symptom is seizures, but not all individuals who have seizures have epilepsy Epileptics have seizures generated by their own brain dysfunction Affects about 1% of the population Difficult to diagnose due to the diversity and complexity of epileptic seizures

The striatum (Basal Ganglia Structures) is thought to store what type of memory

Procedural memories

Brain Infections Viral

Rabies - high affinity for the nervous system Mumps and herpes - typically attack tissues other than the brain Viruses may lie dormant for years

Christopher repeatedly harassed his sister by teasing her, taking items from her room without permission, and yelling at her while she was talking on the phone to her friends. In general trying his best to annoy her. During one of these occasions, his sister took his video game and smashed it. This would be an example of which type of aggression?

Reactive aggression

Electrooculogram (EOG)

Records eye movements seen during rapid eye movement (REM) sleep

Why Do We Sleep?

Recuperation theories Sleep is needed to restore homeostasis Wakefulness causes a deviation from homeostasis Circadian theories Sleep is the result of an internal timing mechanism Sleep evolved to protect us from the dangers of the night

Effects of Sleep Deprivation

Recuperation theories predict... long periods of wakefulness will result in disturbances disturbances will get worse as deprivation continues after deprivation, much of the missed sleep will be regained What does the research indicate?

A patient with brain trauma cannot remember events prior to the trauma. Which amnesia does this symptom indicate?

Retrograde amnesia

Electroencephalogram (EEG)

Reveals "brainwaves"

Reducing the Effects of Shift Changes

Schedule phase delays, rather than phase advances Move from current schedule to one that starts later It is easier to stay up later and get up later than to retire and arise earlier Phase advances are harder, explaining why east-bound travel tends to be more difficult to adjust to

Seizures preceded

Seizures often preceded by an aura, such as a smell, hallucination, or feeling Aura's nature suggests the epileptic focus Warns epileptic of an impending seizure

Brain Infections Viral infections

Some preferentially attack neural tissues

Partial Seizures Simple

Symptoms are primarily sensory or motor or both (Jacksonian seizures) Symptoms spread as epileptic discharge spreads

Brain Infections Bacterial

Syphilis - may produce a syndrome of insanity and dementia known as general paresis Syphilis bacteria are passed to the noninfected and enter a dormant stage for many years

MPTP Model of Parkinson's Disease

The Case of the Frozen Addicts Synthetic heroin produced the symptoms of Parkinson's Contained MPTP MPTP causes cell loss in the substantia nigra, like that seen in PD Animal studies led to the finding that deprenyl can retard the progression of PD

Sleep and Dreaming

The amount of REM increases during the sleep period following learning, and REM deprivation after learning reduces retention. There is increasing evidence from both animal and human studies that non-REM sleep is also important for learning. A study indicated that consolidation is a multi-step process requiring a combination of REM and slow wave sleep.

anterior and posterior

The anterior and posterior circulation communicate in the circle of Willis

Seizure Disorders

The preferred term for epilepsy. Seizure disorders constitute the second most important category of neurological disorders, following stroke.

What is Metastasis tumor?

The process by which cells break off of a tumor, travel through the vascular system, and grow elsewhere in the body.

Which of the following is a good career option for a person with damage to their amygdala?

Trapeze artist working for the circus

The mutual inhibition of the VLPA with various brain stem nuclei may result in:

Alternation between sleep and wakefulness

Encephalitis

An inflammation of the brain; caused by bacteria, viruses, or toxic chemicals.

Studies of Sleep Deprivation in Humans

3-4 hours of deprivation in one night Increased sleepiness Disturbances displayed on written tests of mood Poor performance on tests of vigilance 2-3 days of continuous deprivation Experience microsleeps, naps of 2-3 seconds Little effect of sleep deprivation: Logical deduction, critical thinking Physical strength and motor performance Larger effect of sleep deprivation: executive function (prefrontal cortex) Assimilating changing information Updating plans and strategies Innovative, lateral, insightful thinking Reference memory

REM Sleep and Dreaming

80% of awakenings from REM yield reports of story-like dreams External stimuli may be incorporated into dreams Dreams run on real time Everyone dreams Penile erections are not a result of erotic dreams Sleepwalking and talking are less likely to occur while dreaming

Meningioma

A benign tumor composed of the cells that constitute the meninges

What is a Glioma Tumor?

A cancerous brain tumor composed of one of several types of glial cells.

What is a Malignant tumor?

A cancerous tumor that can cause harm; lacks a distinct border and may metastasize

Cerebro-Vascular Disorders Obstructive stroke (80%)

A cerebrovascular accident caused by occlusion of a blood vessel (internal carotid or vertebrobasilar arteries, MCA)

Cerebro-Vascular Disorders Hemorrhagic stroke (20%)

A cerebrovascular accident caused by the rupture of a cerebral blood vessel.

Treatment for Phenylketonuria consists of early diagnosis and _________.

A diet low in phenylalanine

Down syndrome

A disorder caused by the presence of an extra twenty-first chromosome, characterized by moderate to severe mental retardation and often physical abnormalities.

Rabies

A fatal viral disease that causes brain damage; usually transmitted through the bite of an infected animal.

Physiological Mechanisms of Sleep and Waking Ventrolateral preoptic area (VLPA)

A group of GABAergic neurons in the preoptic area whose activity suppresses alertness and behavioral arousal and promotes sleep. Destruction of this area has been reported to result in total insomnia, coma, and eventual death in rats.

Phenylketonuria (PKU)

A hereditary disorder caused by the absence of an enzyme that converts the amino acid phenylalanine to tyrosine; the accumulation of phenylalanine causes brain damage unless a special diet is implemented soon after birth.

Tay Sachs disease

A heritable, fatal, metabolic storage disorder; lack of specific enzymes that causes accumulation of waste products and swelling of cells in the brain.

Pyridoxine dependency

A metabolic disorder in which an infant requires larger than normal amounts of pyridoxine (vitamin B6) to avoid neurological symptoms

Parkinson's Disease

A movement disorder of middle and old age affecting about .5% of the population Pain and depression commonly seen before the full disorder develops Tremor at rest is the most common symptom of the full-blown disorder Dementia is not typically seen No single cause Associated with degeneration of the substantia nigra, whose neurons release dopamine Almost no dopamine in the substantia nigra of Parkinson's patients Autopsies often reveal Lewy bodies (protein clumps) in the substantia nigra Treated temporarily with L-dopa Linked to about ten different gene mutations Deep brain stimulation of subthalamic nucleus reduces symptoms, but effectiveness slowly declines over months or years

What is a Benign tumor

A noncancerous tumor that does no "harm"; has a distinct border and cannot metastasize. Most brain tumors are infiltrating (healthy tissue) Grow diffusely through surrounding tissue

Suprachiasmatic nucleus

A nucleus situated atop the optic chiasm. It contains a biological clock responsible for organizing many of the body's circadian rhythms.

Melanopsin

A photopigment present in ganglion cells in the retina whose axons transmit information to the SCN, and the thalamus

Disorders of Development Neural adhesion protein

A protein that plays a role in brain development; helps to guide the growth of neurons.

Huntington's Disease

A rare, progressive motor disorder of middle and old age with a strong genetic basis Begins with fidgetiness and progresses to jerky movements of entire limbs and severe dementia Death usually occurs within 15 years Caused by a single dominant gene First symptoms usually not seen until age 40

What are Brain tumors?

A tumor (neoplasm) is a mass of cells that grows independently of the rest of the body - a cancer ~20% of brain tumors are meningiomas - encased in meninges Encapsulated, growing within their own membranes, usually benign, surgically removable

Acute anterior poliomyelitis

A viral disease that destroys motor neurons of the brain and spinal cord.

Herpes simplex virus

A virus that normally causes cold sores near the lips; can also cause brain damage.

Which is not a characteristic of a benign tumor?

A) The tumor is encapsulated B) The tumor grows aggressively by infiltrating other brain regions C) The tumor has a distinct border D) The tumor does not metastasize to other organs in the body

Diagnostic Issues

AD remains a disease of exclusion, with all other possibilities for the clinical presentation being eliminated NPH - develops very slowly in adults >60 yrs of age. Etology is largely unknown, but can result from traumatic injury, or tumor. Symptoms can present very much like A.D. i.e. decline in memory, possible dementia, gait

Risk Factors for Meningitis

Alcoholism HIV Diabetes Sinusitis Acquired immunodeficiencies Overcrowded environments such as day care centers, prisons, college campuses are often foci for spreading bacteria

Comparative Analysis of Sleep

All mammals and birds sleep - must have an important function Not a special higher-order human function Not necessarily needed in large quantities No clear relationship between species' sleep time and activity level

Four Stages of Sleep EEG

Alpha waves -Bursts of 8- to 12-Hz EEG waves -Eyes closed, preparing to sleep EEG voltage increases and frequency decreases as one progresses from stage 1 through 2, 3, and 4 Stage 1 Similar to awake EEG, but slower Low-voltage, high-frequency Stage 2 K complexes - one large negative (upward deflection) wave followed by one large positive wave Sleep spindles - bursts of 12-14 Hz waves Stages 3 and 4 - delta waves, large and slow Progress to stage 4 sleep and then back to stages 3, 2, and (emergent) stage 1 Emergent stage 1 differs from initial stage 1 REMs Loss of body core muscle tone Progress through sleep stages in 90-minute cycles Durations of emergent stage 1 periods lengthen as night progresses Emergent stage 1 sleep = REM sleep All other stages = Non-REM (NREM) sleep Stages 3 + 4 = slow-wave sleep (SWS) During REM sleep: REMs, loss of core muscle tone, low-amplitude/high-frequency EEG, increased cerebral and autonomic activity, muscles may twitch, clitoral or penile erection

Meningitis

An inflammation of the meninges; can be caused by viruses or bacteria. Clinical symptoms include: fever, vomiting, confusion, headache and stiff neck Can lead to severe complications including hydrocephalus, Seizures, or death

Galactosemia

An inherited metabolic disorder in which galactose (milk sugar) cannot be easily metabolized; impairs development of white matter in the brain.

If you were evaluating the emotional response of an individual using the circumplex model and determined that the individual was high on arousal coupled with negative valence, you would say the person was exhibiting which emotion?

Anger

Closed-Head Traumatic Brain Injury

Brain injuries due to blows that do not penetrate the skull - the brain collides with the skull Contrecoup injuries - contusions are often on the side of the brain opposite to the blow

Generalized Seizures Petit mal (aka absence seizures)

Characterized by inattention, may be misidentified as ADD

Circadian Sleep Cycles

Circadian rhythms - "about a day" Virtually all physiological, biochemical, and behavioral processes show some circadian rhythmicity Zeitgebers - environmental cues that entrain circadian cycles

Four Brain Areas for Sleep: Hypothalamus (two areas)

Damage in preoptic area and adjacent forebrain results in wakefulness Damage in posterior hypothalamus and adjacent midbrain results in excessive sleep

Electromyogram (EMG)

Detects loss of activity in neck muscles during some sleep stages

. A patient has been diagnosed with an AVM involving the vertebral arteries that supply the brainstem. Given what you know about brainstem function, what would you expect the patient's impairment to involve?

Difficulty with respiration

Damage Due to Cerebral Ischemia

Does not develop immediately Most damage is a consequence of excess neurotransmitter release - especially glutamate Blood-deprived neurons become overactive and release glutamate Glutamate overactivates its receptors, especially NMDA receptors leading to an influx of Na+ and Ca2+ the release of still more glutamate a sequence of internal reactions that ultimately kill the neuron takes time does not occur equally in all parts of the brain mechanisms of damage vary with the brain structure affected

How are Seuzures diagnosed?

EEG - electroencephalogram Seizures associated with high amplitude spikes

Interpretation of Dreams

Freud's explanation: dreams are triggered by unacceptable repressed wishes Manifest dreams - what we experience Latent dreams - the underlying meaning No evidence for this Activation-Synthesis Modern alternative to Freud's explanation of dreams Dreams due to cortex's attempt to make sense of random brain activity (Hobson, 1989)

Reducing Jet Lag

Gradually shift sleep-wake cycle prior to travel Administer post-flight treatments to promote the needed shift Phase advance following east-bound travel with intense light early in the morning Hamster studies suggest a good early morning workout may also help

According to Joseph LeDoux's cognitive theory of emotion, the pathway dependent on interpretation and evaluation of complex emotions such as guilt is called:

High Road

The amygdala is thought to activate the appropriate sympathetic responses to threat via the __________?

Hippocampus

The Tuberomammillary Nucleus consists of which type of neurons involved in alert behavior?

Histaminergic neurons

Jet Lag and Shift Work

Jet lag - zeitgebers are accelerated or decelerated Shift work - zeitgebers unchanged, but sleep-wake cycle must be altered Both produce a variety of deficits Can the effects be prevented or minimized?

A 57 year old man is brought to the emergency department by local law enforcement personnel. The man is undernourished, and clearly intoxicated. Other indicators, such as a lack of personal hygiene, suggest that the man's condition has been long term. When the physician asks the man where he lives, the man doesn't seem to be able to provide that information. The man is most likely suffering from which of the following?

Korsakoff Syndrome

Circadian Clock: Suprachiasmatic Nucleus (SCN) in the Medial Hypo-thalamus

Lesions do not reduce sleep time, but they abolish its circadian periodicity Exhibits electrical, metabolic, and biochemical activity that can be entrained by the light-dark cycle Mechanisms of entrainment of SCN cells to light-dark cycle Rare retinal ganglion cells with no rods or cones Retinohypothalamic tracts branch off from optic nerve before the optic chiasm

Generalized Seizures Grand mal

Loss of consciousness and equilibrium Tonic-clonic convulsions Rigidity (tonus) skeletal muscles contract Tremors (clonus) Resulting hypoxia may cause brain damage

What is malignant?

Malignant, --meaning they do not have a distinct board, can grow aggressively, difficult to remove or destroy About 10% of brain tumors are metastatic - they originate elsewhere, typically the lungs or breast tissue

Neurotoxins

May enter general circulation from the GI tract or lungs, or through the skin Toxic psychosis - chronic insanity produced by a neurotoxin The Mad Hatter - hat makers often had toxic psychosis due to mercury exposure Some antipsychotic drugs produce a motor disorder called tardive dyskinesia Some neurotoxins are endogenous (produced by the body)

Alzheimer's Disease

Most common cause of dementia - likelihood of developing it increases with age Progressive, with early stages character-ized by confusion and a selective decline in memory Definitive diagnosis only at autopsy - must observe neurofibrillary tangles and amyloid plaques Several genes associated with early-onset AD synthesize amyloid or tau, a protein found in the tangles Which comes first, amyloid plaques or neuro-fibrillary tangles? Genetic research on early-onset AD supports amyloid hypothesis (amyloid first) Decline in acetylcholine levels is one of the earliest signs of AD Impaired olfactory function is another early indicator

Multiple Sclerosis

Multiple Sclerosis A progressive disease that attacks CNS myelin, leaving areas of hard scar tissue (sclerosis) Nature and severity of deficits vary with the nature, size, and position of sclerotic lesions Periods of remission are common Symptoms include visual disturbances, muscle weakness, numbness, tremor, and loss of motor coordination (ataxia) Epidemiological studies find that incidence of MS is increased in those who spend childhood in a cool climate MS is rare amongst Africans and Asians Strong genetic predisposition and many genes involved An autoimmune disorder - immune system attacks myelin Drugs may retard progression or block some symptoms

Twisted protein filaments found in dying nerve cells characteristic of Alzheimer's disease are called:

Neurofibrillary tangles

Anterior circulation

Neurologic deficits reflect the area of brain involved. Anterior circulation stroke typically causes unilateral symptoms. Posterior circulation stroke can cause unilateral or bilateral deficits and is more likely to affect consciousness, especially when the basilar artery is involved.

Brain Infections Bacterial infections

Often lead to abscesses, pockets of pus May inflame meninges, creating meningitis Treat with penicillin and other IV antibiotics

Physiological Mechanisms of Sleep and Waking Neural control of arousal

Tuberomammillary nucleus A nucleus in the ventral posterior hypothalamus, just rostral to the mammillary bodies; contains histaminergic neurons involved in cortical activation and behavioral arousal. Histamine A neurotransmitter implicated in the control of wakefulness and arousal; a compound synthesized from histidine.

Dementia stemming from A.D

Two thirds of all cases of dementia stem from this etiology. Pathology includes: Cell Loss hippocampal cells/medial temporal lobe affected first, but extends to prefrontal regions while sparing primary motor and sensory cortices Pathology includes: presence of neurofibrillary tangles and senile plaques Additional cell loss of ACh neurons which has widespread projections to frontal and temporal lobes Typical distribution of neurofibrillary tangles and amyloid plaques in an Alzheimer's patient's brain

Hemorrhagic Strokes

Usually effects subcortical structures Signs include: extreme headache, nausea, vomiting, focal neuro deficits Associated with hypertension Additionally w/aneurysm (& vasospasm) AVM Tumor ETOH (excessive) Cocaine use

How do you separate the effects of stressors used to prevent sleep from the effects of lost sleep? Does sleep loss affect your performance?

We tend to be poor judges of the effects of sleep deprivation on our performance

Concussions

While there is no apparent brain damage with a single concussion, multiple concussions may result in a dementia referred to as "punch-drunk syndrome" now more formally called CTE Chronic Traumatic Encephalopathy Because of the nature of the neuropathology there is no "gold standard" diagnosis especially for Mild TBI/Concussion There is a rapid onset of short-lived neurological impairments that resolved rather quickly Symptoms may involve LOC but that is not required for the diagnosis Neuroimaging is typically clean Disorder is more "functional" than structural

Cerebrovascular Disorders Stroke

a sudden-onset cerebrovascular event that causes brain damage Cerebral hemorrhage - bleeding in the brain Cerebral ischemia - disruption of blood supply Third leading cause of death in the U.S. and most common cause of adult disability

Carlson has periods of nonresponsiveness, and sometimes stares off into space for brief periods of time. These spells are beginning to interfere with his performance at school. After consulting with a neurologist, it was suggested that Carlson be tested for which seizure disorder?

absence seizure

In the brains of Alzheimer's patients, the level of __________ is greatly reduced.

acetylcholine

. The transition between wakefulness and sleep is marked by the appearance of ________ waves in the sleep record.

alpha

Cerebrovascular Disorders Cerebral hemorrhage

blood vessel ruptures Aneurysm - a weakened point in a blood vessel that makes a stroke more likely; may be congenital (present at birth) or due to poison or infection

Stages of sleep are easily distinguished by:

changes in the electrical activity of the brain.

Pituitary Adenoma

clinical symptoms include changes to hormone systems such as lactation; also could include changes in vision due to compression of optic nerve

Closed-Head Traumatic Brain Injury Contusions

closed-head injuries that involve damage to the cerebral circulatory system; hematoma (bruise) forms when there is disturbance of consciousness following a blow to the head and no evidence of structural damage

Cerebrovascular Disorders what is Cerebral ischemia types?

disruption of blood supply Thrombosis - a plug forms in the brain Embolism - a plug forms elsewhere and moves to the brain Arteriosclerosis - wall of blood vessels thicken, usually due to fat deposits

vertebral and basilar arteries

supply the brain stem, cerebellum, posterior cerebral cortex, and medial temporal lobe. The posterior cerebral arteries bifurcate from the basilar artery to supply the medial temporal (including the hippocampus) and occipital lobes, thalamus, and mammillary and geniculate bodies.

All of the following occur during a stress response EXCEPT:

the parasympathetic branch of the autonomic nervous system is activated.

Brain Infections Encephalitis

the resulting inflammation

GBM - Gliablastoma Multiform

very aggressive, rapid growth, poor prognosis