Lecture 5 Flashcards
what is a hypnotic
drug that induces sleep
what is a depressant
a drug that reduces neuron activity (and arousal)
what is a stimulant
drug that promotes wakefulness and arousal
t/f we do not know if lower lifeforms such as insects sleep
true
rapid eye movements during sleep are found only in
mammals and birds (warm blooded vertebrates)
what does an EEG do
- Records electrical activity in the head
- When neurons fire an action potential, it is electricity that can be picked up by an electrode
can tell a person’s level of consciousness by
the power of their brainwaves
a synchronized wave is
usually high power
when these neurons all fire at the same time
it is a big peak and a big trough, making it a high power wave
we describe stages of sleep based on
the patterns of neural activity in the brain and features of body physiology (muscle tone, heart rate, breathing rate, body temperature)
beta activity
when you are very concentrated
alpha activity
very typical when you are awake, but are not thinking too much
theta activity is
light sleep
- Breathing rate is similar to when we are awake
- Heart rate is also similar
- Easy for us to wake up
sleep spindle
- Important for progressing into deep sleep
- Stage two sleep
- Can be roused, but not as easy as theta activity
- Could also have dreams
K Complex
important for mental housekeeping
delta activity
- Deep sleep
- Waves are synchronous and high power
- Slowest frequency our brain does
N1 is
light sleep with normal breathing and heart rate (brief)
N2 shows
sleep spindles, K complexes, and some delta waves. Breathing & heart rate slow, body temp drops.
N3 is
deep sleep characterized by long stretches of delta waves
REM Sleep
skeletal muscles are paralyzed, breathing shallow and faster. EEG patterns similar to those of wake or light sleep.
- Our brains actually look awake
a typical sleep cycle is
about 90 minutes, but the length of time spent in (NREM) sleep and REM sleep varies through the night, with more NREM initially, and more REM sleep towards morning.