Wait a second!
More handpicked essays just for you.
More handpicked essays just for you.
Effects of sleep on memory
The importance of sleep
The importance of sleep
Don’t take our word for it - see why 10 million students trust us with their essay needs.
Recommended: Effects of sleep on memory
Introduction
Sleep is defined as a reversible, natural state of reduced responsiveness to external stimuli and relative inactivity, accompanied by a loss of consciousness1. This state of inactivity has been evolutionary conserved across species against many selection pressures. This suggests that sleep holds a vital function. Multiple studies have suggested that sleep enhances both declarative and procedural memory 2,3. Consequently, memory consolidation is one of the ostensible functions of sleep. The active system consolidation hypothesis and the synaptic homeostasis hypothesis (SHY) are the two main hypotheses for this putative function of sleep. The active system consolidation model proposes that the repeated reactivation of newly encoded representations in the hippocampus during slow wave sleep (SWS) drives a transfer of memory traces from short-term store in the hippocampus to neocortical regions for long term storage4. These representations are stabilized in the neocortex during subsequent periods of REM sleep by synaptic potentiation5. SHY proposes that sleep acts to homeostatically renormalize synaptic weight to counteract the potentiation that occurs during wake6,7. This occurs by an activity dependent downscaling of synaptic weight during SWS. These models are often portrayed in direct opposition, largely due to the active potentiation proposed in the active system consolidation model, in contrast to the global downscaling (depotentiation) of SHY. However it has recently been considered that these two models may not be mutually exclusive, but could act in unison8. This essay will analyse what I believe to be the best evidence in support and against each model to contend the role of sleep in memory consolidation. The rol...
... middle of paper ...
...urated during previous wakefulness. Napping studies show that SWA enhances the capacity for encoding of declarative memories47. The major function of SHY is the scaling back of energy consumption, once an unsustainable threshold of potentiation has been reached.
Further investigations will be required to elucidate the true role of sleep in memory consolidation. A large amount of evidence has been generated over the last 10 years to support the theory of SHY. There now needs to be a switch toward investigating underlying mechanisms. Altering expression of genes associated with LTP, or optogenetically altering input to specific cells in different sleep stages would provide a deeper understanding of the relationship between potentiation and SWS homeostasis. High resolution monitoring of specific synapses during wake and sleep would allow the greatest assessment of SHY.
All mammals exhibit Rapid-Eye-Movement, or REM, sleep, and yet on certain levels this type of sleep would seem to be disadvantageous. During REM sleep, which is when most dreams occur, the brain uses much more energy than during non-REM (NREM) sleep. (1) This "waste" of energy coupled with the increased vulnerability of this state on account of the body's paralysis at this time suggests that there must be a very important reason, or reasons, for the existence of REM sleep and in extension of dreams. Determining the function of dreams, however, has proved very problematic with many arguments which directly oppose each other. Some of the primary functions of dreaming have been tied to is role in development, its production of neuro-proteins, and also to how it may allow for the "rehearsal" of neurons and neuronal pathways. The influence of dreaming on learning is one of the hottest debates. Some argue that dreams aid in learning, others that dreams aid in forgetting, and yet others that dreams have no effect on learning or memory. That REM sleep seems to aid in development might argue that REM sleep may be connected to learning. It seems that most scientists believe that REM sleep aids in certain memory consolidations although some argue that it actually leads to "reverse learning.
However, in regards to amnesic patients, the SMC has proven to be more widely accepted due to reported results implying that the hippocampus is important in consolidating LTM. In contrast, in anterograde patients, memories can be retrieved through recollection and familiarity. In fact, it has been proposed that the recollection process is mediated by the hippocampus.... ... middle of paper ... ...
However, scientists are beginning to uncover that stress can also inhibit the plasticity and neurogenesis within the hippocampus. By inhibiting these processes, stress can negatively influence the mechanism responsible for memory consolidation in the brain. These effects, if not treated promptly with suitable sleep, could have harmful and damaging effects on nerve cells in the hippocampus. By identifying these effects within sleep deprivation, scientists can formulate new effective drugs and mechanisms to enhance memory impairment caused by sleep loss.
Rasch, B., & Born, J. (2008). Reactivation and consolidation of memory during sleep. Current Directions in Psychological Science, 17, 188-192. doi: 10.1111/j.14678721.2008.00572.x
When most people think of sleep, they think of it as a relaxed but yet not a very important part of our daily lives. What most people don’t understand is although we are not up and moving around and getting tasks completed, our brains are still very active. Without sleep our bodies do not function correctly on a daily basis, and our mental state is at risk.
Many studies of the role of sleep are partial or total sleep deprivation studies which support Oswold’s restoration theory. One of these supporting studies was Dement’s. He deprived participants of REM sleep and consequently found that they increased their number of attempted REM stages from 12 to 26 over 4-7 nights. During their first uninterrupted night, participants increased their REM sleep by 10% which is known as REM rebound. This suggests the importance of REM and the possibility that the purpose of sleep is to get into REM sleep. The participants reported anxiety, irritability and difficulty concentrating which shows that REM sleep is needed to avoid these affects and enable brain recovery which corresponds with Oswold’s theory. Even so, Dement’s study has low ecological validity, it has low population validity because there were only 8 participants and they were a self-selected sample. Participants would probably have shown demand characteristics because the experiment took place in a lab. It also has low mundane realism because people would not usually sleep in a lab and be interrupted repeatedly.
Exploringn a Neurobiological Theory of Dreaming Neurobiological theory of dreaming focuses on the brain and the nervous system. The activation synthesis theory which is one of the theories put forward by Hobson and Mcarley (1998) said sleep is controlled by mechanism in the brainstem. When activated this inhibits activity in the skeletal muscles and increases activity in the forebrain. This theory seems dreaming as an automatic part of the sleep process that may have no significance beyond the need to organize the material into coherent forms. Hobson points out that injection of a drug that increases the action of acetylcholine both increases REM sleep and dreaming.
Have you ever gone to bed and wondered what does sleep do to your physical and mental health? Sleeping has effects on our physical heart as well as our mental health (disorders, etc.)
Sleeping is something that is an essential part of human nature and is a must in order for one to be a functional human being. Sleep is an idea that is accompanied by many wives’ tales, including the idea that one needs seven to eight hours of sleep each night and alcohol helps one fall asleep and sleep more soundly. One myth about sleep is that during sleep, one is in a state of nothingness. In truth, however, it has been discovered that during sleep the brain is active, variations in heartbeat and breathing occur, and the eyes and ears are active throughout the time of sleep. These activities during a person’s sleep are important because they help that person be more aware, awake, and alert during sleep.
Each night, the average person spends approximately 7-9 hours giving their bodies a restful vacation in the land of dreams. Considering this, we spend 1/3 (or 25 years) of our entire lives engaging in this idle activity. Although these numbers can appear as a waste of time in our every day lives, sleeping and/or napping is the energy that helps fuel our bodies to function correctly. Sleep is a necessary function in our every day routine in order to make our brains function at the most efficient level. As we sleep, the brain helps us to recuperate and regain strength by “restoring and repairing the brain tissue” (Myers, 2010, p 99). Without this reviving process, we would all eventually deteriorate. By impairing the sleep deprived mentally and physically, it can potentially cause serious harm. We must fade our conscious mind, and let our mind relax within subconscious state.
From this study, the hours of sleep can have a great impact on my memorize ability, so I do an experiment to test the best sleep time for me to have most effective memory.
In conclusion, the moderately enhanced results leads to think that the naps did have positive effects on all three test results, but not to the extend that was hypothesized. Perhaps a more ordered and organized napping and sleep schedule would allow for greater and more significant improvements. A further analysis in the domain of effects of napping on performance, either cognitive or physical, should strive to measure the impact of tightly arranged schedule to allow for naps to occur at relatively the same time everyday, as well as having a similar length, paired with comparable amount of sleep the night prior to engaging in napping. This would allow assessing the true effects of naps on an individual much more effectively.
We experience two phases of sleep which repeat themselves every ninety to one hundred and ten minutes, achieving approximately five complete cycles per night. The phases are non- rapi...
Sleep is very important to our body for relaxation, preparing ourselves for the next day. Unfortunately, poor sleeping quality is prevalent in modern cities such as Hong Kong. An increasing number of university students have stated sleep problems. (Suen, Hon & Tam, 2008). Meerlo, Mistlberger, Jacobs, Heller & McGinty (2009) have reported that prolonged sleep loss may affect the rate of neurogenesis...
Rasch, Björn, and Jan Born. "About Sleep 's Role in Memory." Physiological Reviews. American Physiological Society, n.d. Web. 06 May 2016.