HUMAN MEMORY

Human Memory



Human Sleep Serves as a Restorative Function

The necessity to sleep has always been a factor of our human lives, present as a part of our daily activities. This activity of sleeping, instinctually occurs from the moment of our births, until we die, behaving as fundamental requirement of regular human functionality. Sleep, by definition, is the natural periodic suspension of voluntary bodily functions and complete or partial suspension of consciousness, during which the powers of the body are restored (Lexico Publishing Group, LLC.). The value and effect of sleep though, has not always been taken into consideration and analyzed.

A comparison of the polygraphs taken during these two stages shows relatively similar eye movement wave-frequencies, but reveals different electrical wavelengths, which indicates a difference in brain activity. In stage one, a polygraph test of a normal person usually reveals low-frequency movement wave patterns that are long and that move up and down in short intervals, these waves are referred to as alpha waves. This reveals a decrease in eye movement and less facial muscle contraction; all signs which show that a person is calming down, and slowly immersing themselves into sleep (Regestein, 1980). In stage two eye movement and muscle contraction has slowed decreased even more so than in stage one Maas, 1998). Significantly different though, the electrical wavelengths have increased in frequency, and show bunched, high peaking vertically increased wavelengths, which reveal burst-like activity. This is important, as is shows that movement has lessened but, electrical brain activity has increased.

Following the transitional twilight stages of sleep from a state of wakefulness, stage three of sleep, or deep restorative, initiates. To a greater extent than stages one and two, deep sleep is categorized by an even more so decrease in body movement; there is hardly any body movement, heart-rate and blood pressure have dramatically dropped and have stabilized at a constant slow rate. All of the higher electrical brain activities of stage two have decreased (Caldwell, 2003). Polygraph test during stage three reveal elongated frequencies of wave-lengths with constant electrical vertical movement of low, intermediate peaks (Maas, 1998). The waves shown in the graphs are now given the name theta waves, and the sometimes appearing slower waves are known as delta waves. These waves and their intensity in regards to their peaks are electrically less active than stage 2, showing a decrease in brain activity. Most importantly, as the name suggest, deep restorative is the portion of sleep in which the human body recovers from it awake activities and allows for growth and development. Blood circulation to the muscles increases, body temperature is turned down to conserve energy, metabolic activity is at the lowest point of the whole day, and growth hormones are developed and secreted (Maas, 1998). The sleep restorative on the whole is known for the restorative and growth-promoting properties, which maintains our bodies functioning properly, and in maintains our general health.

Following deep restorative is the stage of deep sleep. Deep sleep actually coincides with deep restorative, as ...