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Flashcards in Chapter 59 Deck (30):

Define sleep

the unconscious form which the person can be aroused by sensory stimuli.


What are the sleeping patterns of slow-wave sleep?

type is extremely restful and decreases all sympathetic activities.


How long does REM sleep laast?

5-30 mins with phases aat about every 90 mins when ur sleeping


What are the characteristics of REM sleep?

 Involved with active dreaming and active bodily movements.
 Hard to arouse a person from this sleep.
 Muscle tone is depressed.
 Heart rate and respiratory rate become irregular
 Though peripheral muscles are extremely inhibited, there are irregular muscle movements. There are also rapid eye movements.
 Sounds weird, but there is an increase in brain metabolism. This is also called paradoxical sleep cuz even though the person is asleep there is a marked activity in the brain.


What are the 3 locations to induce sleep?

1. Raphe nuclei (releases serotonin into the reticular formation and limbic system)
2. Solitary nucleus
3. Diencephalon (suprachaismatic N.)


What would happen if the raphe nuclei and the superchiasmatic area are lesioned?

the excitatory reticular nuclei of the mesencephalon and the upper pons are released from inhibition, thus causing intense wakefulness.


What is the role of the muramyl peptide?

• Muramyl is a peptide that accumulates in the CSF in animals kept awake for several days.
• Interesting part: when only micrograms of this sleep-producing substance are injected into the 3rd ventricle, sleep occurs within a few minutes. Basically, when you get tired this substance accumulates.


What is the physiological fxn of sleep?

restores both normal levels of brain activity and normal balance among different functions of the CNS. It’s almost like restarting a computer.


When are the freq of alpha waves?

8-13 hz


When are alpha waves recorded?

Found in the EEG’s of awake, quiet, resting state. Occur mostly in occipital region. Goes away when person is sleeping.


Where are alpha waves derived?

Occur in the cerebral Cx only when it has connections to the thalamus. Stimulation of reticular nuclei around the thalamus causes them. They come from spontaneous feedback oscillation of the thalamocortical system.


When are the freq of beta waves?

18-80 Hz


When are beta waves recorded?

Visual sensations cause immediate cessation of the alpha waves and are replaced by beta waves. Most in parietal and frontal lobes.


When are the freq of theta waves?



When are theta waves recorded?

In parietal and temporal lobes, particularly in kids but during times of stress in adults. Also show up in some brain disorders.


When are the freq of delta waves?

< 3.5


When are delta waves recorded?

Occur in very deep sleep, in infancy (sleep like a baby!), and in serious brain disease. Also occur in animals that have had subcortical transections separating the thalamus from the cerebral Cx  they can persist strictly in the cerebral cortex!


Where are delta waves derived?

independently from the cerebral Cx


What are the Sx of grand mal seizures?

o Characterized by extreme neuronal discharges in all areas of the brain, including the cerebral Cx, deep cerebrum, and brain stem.
o Discharges all the way into the spinal cord cause tonic seizures of the entire body, followed by alternating tonic and spasmodic (clonus!) muscle contractions called tonic-clonic seizures.


What are the EEG readings for grand mal?

100μV, high-voltage/high-frequency discharges over the entire Cx bilaterally.


What are the Sx of petit mal seizures?

o Involved the thalamocortical brain activating system. Characterized by 3-30 seconds of unconsciousness or mental “absence” with twitch-like contractions of muscles in the head regions.


What are the EEG readings for petit mal?

50 μV, have spike and dome pattern over entire Cx.


What are the Sx of focal epilepsy?

o Can involve almost any local part of the brain. Results from scar tissue on the brain, tumor of the brain, trauma to the brain or genetics.
o If it happens over the motor Cx, there is a “March” of muscle contractions throughout the opposite side of the body. This is called Jacksonial epilepsy.
o Psychomotor seizure- may cause short period or amnesia, rage, fear and/or motor problems. Typically involves the limbic system.


What are the EEG readings for focal epilepsies?

50 μV, low-frequency rectangular wave with a freq of 2-4 Hz.


What is the physiological cause of depression?

Diminished formation of NE or serotonin or both.
-Locus ceruleus produces NE.
-Raphe nuclei produce serotonin and send axons to the limbic system.


Sx of depression?

Grief, unhappiness, despair, misery, decreased appetite and libido, insomnia.


So there is a decrease in which 2 NT's to cause depression?

NE and serotonin


What are the 3 causes of schizophrenia?

1. Prefrontal lobes glutamate inputs are blocked.
2. Excessive excitement of dopamine neurons onto frontal lobes. This is a problem with treating Parkinson’s with L-DOPA.
3. Abnormal functioning of the limbic behavioral control system of the hippocampus.


What forms in the brains of alzheimers pts to cause the disease?

There are increased amounts of beta-amyloid peptides in the brain. This forms widespread amyloid plaques. This is from mutations that increase the beta-amyloid production


Pt's who are at risk for what disease are also at risk for alzheimers?

vascular disorders like HTN and atheroscerosis