Why is the minimally conscious state considered a higher stage of consciousness than the vegetative state?

Here is a link to information about locked-in syndrome, which is terrifying and fascinating. (but not in our text). Based on this table and our text,
a) What is the difference between brain death and coma?
b) Why is the minimally conscious state considered a higher stage of consciousness than the vegetative state?
c) Once brain activity ceases, why do you think physicians test for brain activity again 24 hours later before pronouncing brain death?
d) Why is locked-in syndrome terrifying to patients?
2. What two things does a polysomnograph record?
3. The stages of sleep are human-created distinctions among the recordings you see on a polysomnograph record. In other words, humans decided which type/pattern of waves indicated relaxation, Stage 1, Stage 2, etc. You’re expected to be able to describe the brain waves associated with each stage. Record your descriptions below. Words to include: the waves’ voltage (how tall are they?), frequency (how much space is between the waves), how they compare to other stages, special features of that stage, etc. Also, what would you look for to identify that stage in records like those included in Fig. 8.11.
Stages 1-4 are considered non-REM (NREM):
a) Stage 1
b) Stage 2
c) Stage 3
d) Stage 4
And then there is REM:
e) REM
4. And some questions about the stages, taken together:
a) Why are Stage 3 and Stage 4 sometimes combined into one stage called slow-wave sleep (SWS)?
b) Why is REM also called paradoxical sleep?
c) How would you know that a person is in REM sleep?
d) Study Figure 8.12. During which part of the night is REM most prevalent? During which part of the night is SWS most prevalent?
Part 2a – Brain Structures in Sleep and Wakefulness
Summarize the important details about the following brain structures involved in wakefulness:
1. pontomesencephalon:
neurons here get input from _______________ and they are also spontaneously active (without input)
neurons here send output to 3 forebrain areas: ________________, _________________, ___________________
neurotransmitters __________ and _____________ are released from pontomesencephalon cell axon terminals onto neurons in these 3 forebrain areas—does that cause excitation or inhibition?
the 2 roles of the pontomesencephalon relative to arousal are:
2. locus coeruleus:
neurons here are excited by ______________ events that produce _______________ arousal
these neurons send output all over the _____________
this output causes 2 things to happen to the activity of cortical cells:
in terms of functioning, 2 things are enhanced by locus coeruleus activity:
3. hypothalamus:
some of these neurons release histamine as their neurotransmitter—what does it do in the brain?
others of these neurons release orexin (hypocretin) as their neurotransmitter—what does it do in the brain?
do we need orexin to wake up? do we need orexin to stay awake?
4. basal forebrain:
neurons here send axons to 2 brain areas:
they release the neurotransmitter __________________ which (increases or decreases?) _______________ arousal
when this NT is released, what is the effect on cognition?
Summarize information about the role of these brain areas in sleep:
5. thalamus:
what happens to the polarization of neurons in the thalamus during sleep?
how does that influence their sending of sensory information to the cortex?
6. axons that release GABA as their neurotransmitter:
how does their activity change during sleep?
what is the impact of that change on communication among neurons?
how does it affect the sleeping person’s response to stimulation?
what is local sleep, and how could it account for sleep walking?
And finally regarding REM sleep,
Which 2 brain areas show increased activity during REM?
Which 3 areas of the cortex show decreased activity during REM?
Which 2 areas of the cortex show increased activity during REM?
What are PGO waves?
How does acetylcholine affect REM?
How do serotonin and norepinephrine affect REM?
Part 2b – Sleep Disorders
Briefly describe what happens in the brain when a person experiences the following sleep disorders, as well as their symptoms:
1. sleep apnea
2. narcolepsy
3. REM behavior disorder
Part 3a – Important Functions of Sleep
In the table below, list the functions of sleep (why we do it) based on what is said in four sources: Sleep & Dream (video 10:40), The Science of Sleep (video 18:20), Why Sleep is Critical for the Body and Brain (video 14:11), and chapter 8 of our text. (There are links to the videos in the Overview page of the module.)
Some functions are mentioned in several of the 4 sources; others may be mentioned in only one. Make sure to listen carefully so that your table will be complete.
Functions of Sleep
Sleep & Dream
Science of Sleep
Why Sleep is Critical
Text Chapter 8
Supports growth
yes
yes
yes
no
Now study your table. Based on what you have gleaned from these four sources, what would you consider the most important function of sleep? Justify your choice.
Part 3b – Biological Basis of Dreaming
1. How does the activation-synthesis hypothesis explain dreaming? According to this idea, what is going on in the brain when we dream?
2. How does the clinic-anatomical hypothesis explain dreaming? According to this idea, what is going on in the brain when we dream?
3. The video Sleep & Dream describes two biological perspectives on dreaming, the “physiological function” theory and the “REM triggers neural activity” theory. How do these relate to the activation-synthesis hypothesis and the clinic-anatomical hypothesis? Are they completely different theories? Are they the same, just with different names? Explain.

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