Consciousness, Higher Brain Functions, Neurocognitive Disorders

Front 1

Arousal

Back 1

degree of sensory stimulation required to keep an individual at optimum level of cognitive function. Controlled by reticular activating system that extends from lower third of pons to thalamus.

Front 2

Consciousness

Back 2

state of awareness of self and environment. Made of two components: arousal and content (emotion and thought).

Front 3

Sleep

Back 3

active, recurrent, physiologic state that includes a reduction in consciousness and necessary fro health/well-being

Front 4

Non-REM sleep

Back 4

sleep stages N1, N2, N3 (slow-wave sleep).

Front 5

REM sleep

Back 5

Rapid eye movements, dreaming, increased respiratory rate/ body temp / blood flow / O2 consumption / penile erection. Muscle tone is absent. This type of sleep is not required but preferred.

Front 6

Control of Wakefulness

Back 6

locus ceruleus (NE), raphe nuclei (5-HT), tuberomammillary nucleus (H1), ventral periaqueductal gray matter (DA), some basal forebrain/brain stem (Ach), and hypocretinergic lateral hypothalamus

Front 7

Control of Sleep

Back 7

Reduction in neurons firing in wakeful centers, increase GABA firing

Front 8

"sleep factors" that build up in the brain

Back 8

adenosine, nitric oxide, prostaglandin D2.

Front 9

Attention

Back 9

cognitive function, focusing on relevant stimuli and ability to shift to other stimuli as they become relevant.

Front 10

Delirium

Back 10

Primarily due to a disorder of attention. Can have a disturbance of consciousness, decreased cognitive abilities, or hallucinations. Subacute onset.

Front 11

Lesions in ________ areas can lead to delirium.

Back 11

NE and ACh neurons in brain stem reticular activating system and basal forebrain.

Front 12

Lethargy

Back 12

abnormal state which the patient can be aroused with mild (non-noxious) stimulation

Front 13

Stupor

Back 13

abnormal state which the patient can be aroused with only vigorous/forceful/often noxious stimulation and still be cognitively impaired.

Front 14

Coma

Back 14

abnormal state which the patient cannot be aroused even with vigorous stimulation. Different from sleep in almost all ways.

Front 15

Lesion in the basis pontis

Back 15

Locked-in state. Normal consciousness but paralyzed, preservation of vertical eye movements

Front 16

Diffuse cerebral cortical lesion

Back 16

vegetative state. normal arousal and sleep cycles. No higher brain functions.

Front 17

Bilateral medial frontal lesion.

Back 17

Akinetic mutism. normal arousal and sleep cycles. Some higher brain function but inability to initiate thought, movement, and speech.

Front 18

Lesions in these two areas can produce impaired consciousness (stupor or coma).

Back 18

Reticular activating system or both cerebral hemispheres.

Front 19

Focal supratentorial lesion with herniation

Back 19

Decreased consciousness from "pressure dysfunction" causing pushing on the brain stem

Front 20

Focal lesion of reticular activating system (diencephalon, midbrain, pons)

Back 20

decreased consciousness, clinical picture of focal brain stem dysfunction that does not fit picture of cerebral transtentorial herniation.

Front 21

Diffuse or multifocal lesion of bilateral cerebral hemispheres

Back 21

Most common cause of impaired consciousness.

Front 22

CNS depressant dose dependent degree of depression

Back 22

Sedation --> sleep induction --> Loss of consciousness --> anesthesia --> Coma --> fatal depression

Front 23

Difference between barbituates and benzodiazepines with regards to CNS depression.

Back 23

Overdose with benzodiazepines does not cause fatal respiratory depression or coma while barbituates can.

Front 24

Benzodiazepines

Back 24

Enhance GABAa. Highly effecatious sedative hypnotic used for insomia. Can have psychomotor impairment, anterograde amnesia, tolerance, physical dependence, rebound insomnia.

Front 25

Zolpidem

Back 25

Novel benzodiazepine receptor agonists - bind to GABAa R. Most widely prescribed hypnotics - fewer deleterious effects.

Front 26

Ramelteon

Back 26

melatonin R (MT1 and MT2) agonist. Maintenance of circadian rhythm, help to initiate sleep. Far less efficacious than GABA acting drugs.

Front 27

Suvorexant

Back 27

orexin (hypocretin R antagonist). Used for tx of insomnia.

Front 28

Barbituates

Back 28

Bind to allosteric site on GABAa. Dangerous side effects lead to low use as sedative - hypnotics

Front 29

diphenhydramine

Back 29

first generation antihistamines (H1). May decrease sleep latency but not proven to increase total sleep. Residual daytime sedation, some anti muscarinic AE.

Front 30

Drugs used for insomnia

Back 30

Benzodiazepines, barbituates, ramelteon, suvorexant, diphenhydramine

Front 31

MOA of drugs used for insomnia

Back 31

enhance GABAa transmission, melatonin receptor agonists, H1 R antagonist

Front 32

Stimulants

Back 32

psychoactive drugs that temporarily improve mental/physical function. Can improve mood, reduce anxiety, lead to euphoria, stimulate respiration, suppress appetite.

Front 33

Four most common stimulants

Back 33

caffiene, theophylline, theobromine. Agonist activity at adenosine A1 and A2. Nicotine - nicotinic cholinergic receptors.

Front 34

Amphetamine

Back 34

taken up by DAT, NET, SERT and interferes with VMAT increasing catecholamine release. Increases arousal, decreased need for sleep, euphoria, psychosis. Tx: ADHD, narcolepsy

Front 35

Methylphenidate

Back 35

inhibits NET and DAT. Tx: ADHD, narcolepsy

Front 36

atomoxetine

Back 36

inhibits NET. Not a psychostimulant but increases alertness in ADHD.

Front 37

Modafinil

Back 37

psychostimulant inhibits both NET and DAT. Reduces sleepiness with low abuse potential. Tx: narcolepsy, shift-work sleep disorder, obstructive sleep apnea

Front 38

Sodium oxybate (GBH)

Back 38

CNS depressant, analog of GABA acting at GBH receptors. Improves quality of sleep. Tx: narcolepsy, severe cataplexy (transient attach of muscle weakness)

Front 39

Drugs used to promote wakefulness

Back 39

Modafinil, amphetamines, methylphenidate, sodium oxybate

Front 40

Drugs used to promote attention

Back 40

Stimulants (amphetamines, methylphenidate), nonstimulants (atomextine, buproprion, clonidine)

Front 41

Desirable effects for anesthetic

Back 41

induction of anterograde amnesia, skeletal muscle relaxation, inhibition of undesired autonomic reflexes, analgesia

Front 42

Thiopental

Back 42

Enhance GABAa, barbituate, IV general anesthetic

Front 43

Propofol

Back 43

Enhance GABAa, IV general anesthetic

Front 44

Etomidate

Back 44

Enhance GABAa, IV general anesthetic

Front 45

Benzodiazepines

Back 45

Enhance GABAa, IV adjuvant anesthetic drug to initially depress level of consciousness to produce amnesia or reduce anxiety

Front 46

Fentanyl

Back 46

mu opioid receptor agonist. IV Adjuvant anesthetic used for analgesia. Effects reversible by naloxone.

Front 47

Ketamine

Back 47

NMDA antagonist. IV Dissociative anesthetic - dissociates patient from environment.

Front 48

Desflurane

Back 48

Likely act at GABAa. Inhaled general anesthetic

Front 49

Nitrous oxide

Back 49

weak NMDA antagonist. Weak depressor of consiousness. Inhaled anesthetic.

Front 50

Succinylcholine

Back 50

Depolarizing neuromuscular blocking agent.

Front 51

Vecuronium

Back 51

Competitive inhibition of ACh receptors, neuromuscular blocking agent.

Front 52

Typical pattern of brain hemispheric specialization

Back 52

Left dominant for propositional language. Right dominant for nonverbal, spatial abilities. 30% chance of being reversed in left-handed or ambidextrous.

Front 53

Left hemispheric control

Back 53

propositional language, analyzing complex stimuli (details), analyzing temporal sequence

Front 54

Right hemispheric control

Back 54

Processing non-verbal/visuospatial information, synethesizing diverse parts into a whole (big picture), processing spatial information

Front 55

Brocas area

Back 55

inferior frontal gyrus (Left), controls muscle of speech and PRODUCTION of all forms of language

Front 56

Wernickes area

Back 56

superior termoral gyrus (Left), COMPREHENSION of all forms of language

Front 57

Angular gyrus and supramarginal gyrus

Back 57

Involved with reading and writing

Front 58

Lesion in left hemisphere or thalamus

Back 58

Aphasia - acquired disorder of language. Anomia - inability to name a recognized object

Front 59

Lesion in angular gyrus or supramarginal gyrus

Back 59

alexia - acquired disorder of reading. Differs from dyslexia which is a congenital reading disorder. May also have agraphia - acquired disorder of writing.

Front 60

Lesion in Broca's area (inferior frontal gyrus)

Back 60

Aphasia. Patient has slow, effortful speech, that is telegraphic. All other forms of output (writing, signing, foreign languages) are also affected. Comprehension is preserved.

Front 61

Lesion in Wernickes area (superior temporal gyrus)

Back 61

Aphasia. Speed of speaking normal but often uses wrong words or word-like sounds (paraphasic error). Often incomprehensible. Patient's comprehension of auditory and visual language is impaired

Front 62

Lesion in the right hemisphere or parts of motor basal ganglia. Same disorder seen in Parkinson's disease.

Back 62

Aprosodia. Speech lacking emotion of affection, loss of melody. Sounds like a robot.

Front 63

Lesion in right cerebral hemisphere or right thalamus

Back 63

Hemi-inattention. Neglect of left space. No visual field defects, but ignores everything perceived to be in their left field. May also have constructional apraxia - inability to put parts together into a whole

Front 64

A lesion in the right or left cerebral hemispheres or thalamuses can cause this inability to copy drawings despite having comprehension of the task.

Back 64

constructional apraxia

Front 65

Bilateral lesion of occipital temporal visual system (sparing visual area)

Back 65

Visual agnosia - inability to recognize objects despite normal visual acuity. Can recognize objects when presented auditory/tactile. Ex. patient can copy the image of a pig, will know its an animal, but cannot recognize the animal. If the patient hears "oink-oink" they know that's a pig.

Front 66

Lesion of medial prefrontal lobe

Back 66

difficulty initiating and sustaining motor acts. Appear apathetic / indifferent, decrease in spontaneity.

Front 67

Lesion in orbital prefrontal lobe

Back 67

socially disinhibited, ignore long-term needs, live in the present, unconcerned about pain/death

Front 68

Lesion in dorsal prefrontal lobe

Back 68

inability to deal in abstractions, difficulty changing strategies. Preservation - repetition of old behavior. Inability to plan for future.

Front 69

Medial temporal lobe structures (hippocampal formation) important for memory

Back 69

Parahippocampal gyrus, subiculum, hippocampus, dentate gyrus. All part of cerebral cortex.

Front 70

Lesion in any of medial temporal lobe structures (usually diffuse)

Back 70

basic amnesia syndrome - inability to learn new facts (short-term memory), retrograde amnesia, intact procedural memory, confabulation

Front 71

Medial diencephalic structures

Back 71

Mammillary nuclei, important for memory and dependent of vitamin B1

Front 72

Lesion in left medial temporal lobe or left medial diencephalic structures

Back 72

inability to form memories of verbal facts and events. (right sided lesions = inability to remember non-verbal facts/events)

Front 73

Major cognitive disorder

Back 73

significant cognitive decline in one or more domains, substantial impairment on cognitive testing, interference with independence in daily activities, cannot not be due to delirium or other mental disorder like depression.

Front 74

Types of hallucinations

Back 74

release hallucinations (spontaneous neuronal firing), due to neurochemical effects (5-HT2A, Anticholinergic, excess DA), dreams, ictal, from migraines, psychotic (schizoprenia, PTSD)

Front 75

Delusions

Back 75

firmly held false belief despite evidence to the contrary. Always psychotic. Can result from lesion or neurological disorder.

Front 76

Psychosis

Back 76

Loss of ability to determine what is reality. Secondary to neurological lesions in cerebral hemispheres or thalamus

Front 77

Conversion symptoms

Back 77

relatively persistent loss in sensory or motor function that cannot be explained by a physical disorder. Caused by "self-hypnosis"

Front 78

Factitious disorder

Back 78

patient intentionally falsifies or produces physical/psychological sx, but does not know why they are doing it. Muchausen syndrome is an extreme form where patients constantly hospitalize themselves.

Front 79

Malingering

Back 79

conscious faking of neurological or other illness, typically done for a specific purpose. Legal rather than medical problem.

Front 80

Haloperidol

Back 80

D2 receptor antagonist. First gen Antipsychotic. Decreases DA activity in mesocortical/mesolimbic pathways in the VTA.

Front 81

Quetiapine and Aripiprazole

Back 81

D2 antagonist + 5-HT2A antagonist. 2nd gen antipsychotic.

Front 82

Donepezil

Back 82

cholinesterase inhibitor. Tx: cognitive impairment from Alzheimers, only modest effect since impairment not solely from decrease in ACh in basal forebrain.

Front 83

Memantine

Back 83

low affinity NMDA R antagonist. Tx: cognitive impairment from Alzheimers, modest effect.