Sleep Patterns Lab Report

HOW CAN AN INDIVIDUAL’S SLEEP PATTERNS BE MEASURED? BRIEFLY DESCRIBE THE ELECTRICAL PATTERNS OF THE BRAIN OBSERVED DURING THE SLEEP WAKE CYCLE. EXPLAIN THE IMPORTANCE OF SLEEP.

Until the 1930s there was no way to measure brain activity during sleep in an objective or scientific way until the invention of the electroencephalography (EEG). This device is able to measure electrical fluctuations within the brain over a period of time. When measuring sleep patterns EEGs are used along with other devices, the Electromyogram (EMG) a device used to record muscle activity, also observations of patterns and directions of eye movements can be recorded using an electrooculogram (EOG) and related to sleep stages. Equipment such as EGGs measure electrical

This is shown by the EMG. 1937: Loomis et al discovered that in Stage 2 EEG waves become slower and larger, with some quick bursts of high frequency waves called ‘sleep spindles’. Stage 3 then shows even slower and larger waves, and stage 4 has the largest and slowest waves of all because it is the deepest stage of sleep. Metabolic activity is pretty low in general and the sleeper is harder to wake up. After stage 4 the cycle reverses back through stages 3 and 2. A period of active sleep occurs instead of stage. During the active stage metabolic activity increases, and the body appears almost paralyzed except for ‘rapid eye movements’ (REM) a term coined by Aserinsky & Kleitman. The EEG pattern is almost like when you’re awake. The cycle is repeated five times during the night, but we only enter stage 3 and 4 the first two Period of REM increase with each cycle. Self-reports are also used and involve the participant keeping a record of their dreams or estimating their length. They’re useful for gaining information which could not be collected in any other way, but they are limited to accuracy of recall. In each of these methods Variables, such as noise and distraction, are controlled to increase reliability of the research. However, research in sleep labs creates an artificial environment, which may affect the participants sleep patterns and so reduce validity.

One of the

Webb suggests that everyday sleep is similar to hibernation, sleep is a way of conserving energy at times when it is hard to gain resources. For example it is hard for Neanderthal humans to gather food+ at night because it is dark, so they conserve the energy at night by sleeping as using energy would be inefficient. Whereas Meddis suggests that sleep helps to keep animals safe. By being quiet and still, they are less likely to attract predators, however they are more vulnerable if discovered and so we have developed sleeping patterns that minimise that times we are at risk. By moving through the sleep cycle in waves we are only in deep sleep and vulnerable for 10 minutes at a time, rather than being in this state continuously for long periods of time. There are strengths with this explanation. The evolutionary approach focuses on survival and environmental adaptation, is useful for understanding how and why the behaviour occurs. Behaviours have evolved to help survival and adapt to our environment. However it is criticised because evolution occurs over long periods so it’s hard to test theories about why some behaviours have been naturally selected, therefore it’s difficult to prove them wrong, making them less useful from a scientific perspective meaning it has no falsifiability.

Restoration Approaches argue differently. They suggest that sleep restores the body’s ability to function after