Notesale: Turn your study into money

Document Preview

Extracts from the notes are below, to see the PDF you'll receive please use the links above

---

Neuro Midterm 3 Review Notes
*Sleep/Circadian Rhythms, Hypothalamus, & Limbic System

Circadian Rhythms
Suprachiasmatic Nucleus (SCN)






Gets light information from pineal/retina/optic nerve
and gives it to the hypothalamus
o Light is the most influential factor for
biorhythm
o Also influenced by physical activity, feeding,
body temperature, and sleep-related
hormones
Located in hypothalamus, ABOVE optic chiasm
Malfunction in SCN causes you to wake/fall asleep
repeatedly
Retinohypothalamic pathway: Axons of retinal
ganglion cells, known as non-image-forming (NIF) cells, leave the OPTIC NERVE and
project to the SCN
...
Wake Brain Activity










Awake: desynchronized neural activity, high frequency, low voltage
Sleep: synchronized neural activity, low frequency, high voltage
o Neurons fire more like a seizure
...

o Voltage is HIGH, activity is slow
...

REM stages become longer as SWS becomes lighter
...
slow-wave oscillations in brain electrical activity,
o 2
...
changes in synaptic connectivity
Prediction that animals who dream in a larger percentage are smarter than animals that
don’t; sleep study
SLOW WAVE SLEEP = LOW RESPIRATION

Dreaming


PGO Spikes (Pons Geniculate Occipital)
o PGO waves from the brainstem go to visual part of thalamus and into occipital
lobe
 Causes RAPID EYE MOVEMENT characteristic of REM
o They drive dreaming and visions in dreams











o Mostly acetylcholine neurons
that turn on other act
...


While awake, acteylcholine is active (like during the day)
o Then you lay down and fall asleep; when you fall asleep and go to slow wave
sleep (you aren’t thinking)
Aminergic neurons very active (norepinephrine, serotonin, dopamine) these take you
into slow wave sleep
o Aminergic inhibition goes down and cholinergic excitation goes up for REM
o Dreaming thought is very illogical
o Dreaming in slow wave sleep tends to be thoughts that are more logical
o Movements are involuntary
o Episodic movement
Transitioning - CNS trying to get everything to happen at the right time and sometimes it
doesn’t








o REM Sleep
 Stop moving
 Brain is commanding movement because it is active (BUT)
 Movement is inhibited
 Thinking is not logical (if you’re a lucid dreamer you care, if not, you
don’t)
 Internally generated - stirring up memories
 Usually recurring dreams are an “easy memory trace”
 Usually we have a common room or feeling in dreams
Another diff between SW and REM is serotonin turns off, hallucinogens turn these off &
cause synthesia - you’re reproducing the effect
Usually when you enter to REM you make body change and another when you come out
When people take anti-inflammatories, over counter sleep meds, etc
...
Cholinergic
neurons
Animals that live in water often sleep with one
hemisphere at a time – ex
...
Every now and then it’s normal/okay
...
If it happens every few days it could be a
tumor or a stroke
...
These
inhibit skeletal mononeurons, which case REM sleep atonia
...
Evening people
Inherited preference in biorhythm
o Morning types get up early, perform mentally and physically best in the morning
hours, and go to bed early
...

Downside for evening people – they often struggle with poor sleep quality, nightmares,
and dysfunction more often than morning people

Random Things








Being in SWS makes you think you’ve been asleep longer
Your estimation in the MORNING will be more accurate than if you wake up at midnight
o More REM in morning helps you realize it hasn’t been as long
Adults awake with REM recall 90% of the time
20% of the time for children under 8 years old
Children don’t usually have dreams with themselves as character until 8+ years of age
Lucid dreaming is a wiring difference that is INHERITED
Parietal/Temporal activation in people that recall their dreams better on a regular basis



Adenosine debris build up in the early morning because of the longer stages of REM in
those hours; Caffeine inhibits Adenosine receptors on Acetylcholine neurons to help get
rid of drowsiness

Sleep & Health



Chronic sleep loss is highly correlated with depression and anxiety
Improved sleep structure helps improve depression/anxiety

Sicknesses/Immune System
 More sleep = better immune system
 Cytokine production causes INFLAMMATION
Kleine-Levin syndrome
o The onset occurs with an influenza-like illness with upper airway infection and
an acute mild febrile affection, including tonsillitis
...

o The attacks of hypersomnolence usually occur and end suddenly, lasting from
several days to several weeks
...

o Megaphagia, or binge eating, with rapid consumption of large amounts of food,
is the second characteristic of this syndrome

---