Sleep & Dream Flashcards
Describe and comment the various mechanisms of sleep and dreams
With the help of the polygraph, a machine that collects and records data from various devices that are attached to a person sleeping, the sleep researchers have categorized sleep in to 4 stages.
First stageof sleep has beta activity, meaning the person is still alert.
At all the other stagesthe EEG shows a progressively drop in frequency and a higher amplitude. In stages 3 and 4 the brain begins to produce slow and deep waves, thus, the sleep on those stages is called slow-wave sleep. And at stage 4 it consists mostly of delta activity, characterized by high-amplitude waves.
Different brain regions play a role in sleep and biological rhythms: circadian rhythm, is a natural process that follows a 24-hour cycle. Basic rest activity cycle is a 90-minute cycle of rest and activity.
When we wake up, we are experiencing an effect that is similar of the sleep deprivation, it is called sleep inertia effects. Normally it takes 20 to 30 minutes to be fully conscious.
There are many good attributes linked to sleep. The sleep- dependent memory consolidation allows us to consolidate what we learned during the day. Slow-wave sleep helps to remembering words and locations. And rem sleep seems to help implicit and emotional memory.
Dreams occur during the REM phase of sleep and are similar to a play, they have a narrative form. Slow wave sleep and REM sleep reflect two different states of consciousness.
During slow-wave sleep mental activity decreases rapidly and involves situations rather than stories. Reports of people walking up during REM or slow wave sleep show that people are conscious during sleep even though they don’t recall any of their experiences.
