By Cindy J. Velasco
PSY/240 The Brain, The Body, and The Mind
Mr. Lowell Brubaker
March 21, 2013
There are three ways that sleep is measured by using, EEG- Electroencephalogram, EOG- Electrooculogram, and EMG- Electromyogram. In order to measure sleep they use EEG, EOG, and EMG to categorize the sleep stages. As we sleep we hit four different stages of sleep. The first stage is stage 1 EEG or initial stage 1 EEG which is described as a low-voltage, high-frequency signal that is similar to, but slower than that of alert wakefulness. During the progression from steps 1, 2,3 and 4 there is a slow increase in EEG voltage and a drop in the frequency of EEG. Stage 2 has a slight higher amplitude and a lower frequency compared to stage 1 EEG, it also has two wave forms K complexes and sleep spindles. K complexes is a large negative wave or upward deflection with an immediate large positive wave or downward deflection. Stage 3 EEG also known as Slow-wave sleep (SWS) has the occasional presence of delta waves which are the largest and slowest EEG waves. Stage 4 EEG which is also part of (SWS) has predominately delta waves, and you shall remain at stage 4 for some time. After the initial four steps, you will return back to stage 1 EEG but this time it is accompanied by REM's which come with the loss of core muscle tone. This is now called Emergent stage 1 EEC or REM sleep. During the REM sleep is where we have our most vivid dreams that become stories or narratives when we recall them. There are five common beliefs about dreaming. One external stimulation can become part of your dream, this is true if water is splashed on you while REM sleep the water becomes part of you dream . Two dreams last only for an instant, this is not true dreams run on real time. Three some people claim that they do not dream, this is untrue if awaken during REM sleep they do report dreams only difference they dream less. Four penile erections are
References: Pinel, John P.J. (2011). Biopsychology as a Neuroscience 8th edition. Allyn & Bacon: Pearson Education Inc. Chapter 14 Why Do We Sleep, and Why Do We Sleep When We Do.