Thursday, August 22, 2019
Reticular Activating System Essay Example for Free
Reticular Activating System Essay He believed that Dreams are the guardians of sleep. He also believed that they provided an insight into the motives of a persons behaviour. He described it as the royal road to the unconscious. He believed that no matter how absurd a dream was it always possessed meaning and logic. He warned that dreams had to be analysed in the context of a person s waking life. According to Freud the mind had 3 components. Id: This is concerned with basic instinctive urges such as the need for food, comfort and sexual gratification. It works at an unconscious level. It is not driven by logic and is the pre-socialized part of the personality. He felt that we are driven by unconscious urges, and that through dreams the unconscious desires are expressed, Thus relieving psychic tensions. The Id works on the Pleasure principle Superego: Its components are the conscience. This threatens the Ego with punishment, in the form of guilt, for bad behaviour. The other component is the ego-ideal which promises rewards, in the form of pride and high self esteem, for good behaviour. This is developed throughout childhood. This part represents the moral part of the personality and wishes to do the decent/right thing. This is a part of the id that has been modified by influences of the external world. This is the decision maker, working on a rational and logical basis. The demands of immediate gratification by the Id will be postponed by the Ego until the appropriate time and place. It is not imposing constraints on moral grounds; its priority is the CONSEQUENSES of behaviour This works on the reality principle. Freud believed that behaviour is an interaction of these 3 systems. With the Id being repressed by the Ego and Superego, causing anxiety during waking hours. During dreams the Superego is partially asleep And the Id can get through. The Superego Disguises the Id thoughts, (to stop nightmares. ) Dreaming, he saw as protecting sleep, by Providing an outlet for disturbing and repressed Thoughts, in a modified form, without them coming Into consciousness. The contents of dreams were referred to as: Latent This is the real meaning of a dream. These would be conflicts or dis. Thought. Manifest This is what you actually dream. He Argues that this is a censored and symbolic. Although Jung had been a close colleague of Freud, helping him form the psychoanalytic movement, in 1913 he broke ranks. He did not agree that all dreams are wish-fulfilments. He believed that they were a way of acquiring self-knowledge and to restore our psychological balance. He stated that they were just as likely to point to the future, (by suggesting solutions), as to the past. He did agree that dreams can reveal parts of the self that are usually concealed during waking hours. He believed that the Id expresses desires through daydreams. He preferred to take a dreams at face value and also to study dream series rather as opposed to an individual dream. WEBB CARTWRIGHT p Problem-solving theory of dreaming They believe that dreams are a way of identifying and working through problems of the waking life. They do not believe that the true meanings of dreams are disguised and therefore do not distinguish between the latent and manifest content. However the use of metaphor is included in their theory. 4 Problem Solving theory cont. A number of studies support this theory. (cartwright,1978), presented people with common problems. Those who were allowed to sleep uninterrupted later made far more realistic suggestions towards a solution than those who had been deprived of REM sleep. Hartman 1973, showed that people suffering from occupational or relationship problems enter REM sleep earlier and spend longer in it than less troubled subjects. EVANS p Reprogramming theory of dreaming According To Evans during REM sleep the brain shuts off from the external world, isolating itself from sensory input. This time is spent sorting through new data and updating existing memory systems. A number of studies have shown that REM sleep increases following mental activities of a complex nature. Herman Roffwarg 1983, also supported Evan s theory. In their study participants wore distorting lenses during their waking day. These made everything appear upside down. This took a great deal of mental effort to adjust to. 5 Sup. for Evan s theory cont. Herman Roffwang 1983 cont Subsequent monitoring revealed an increase in periods of REM sleep. Evan s theory has also been supported by the findings of older people spending shorter periods dreaming. Neurobiological Approach HOBSON McCARLY 1977 Activation synthesis Theory of Dreams They proposed that dreaming begins with the random firing of giant cells, located in the R. A. S. of the pons, which in turn activate adjacent nerve cells. These include those concerned with vision, motor activity and emotion. This activity also reduces the tone of major muscles, producing temporary paralysis. This prevents us acting out our dreams. Morrison 1983, found that cats with damage to the brain stem actually chased the subject of their dreams and ignored real mice. Although the body is not moving, the cerebral cortex is still receiving information, originating from the giant cells, which suggests it is. In an attempt to make sense of the random activity it merges or synthesises it, using memory to create a dream. Activity of nerve cells involved in balance for example may evolve as dreams about falling. 6 Some have argued that if dreams were merely a meaningless bi-product of random firing of nerve cells they would not reflect our daily experiences, as they often do. Hobson and McCarley argued that the areas of the cortex that have been most recently stimulated during the day are also most likely to Ã together with the brain persistently seeking to find meaning, even if there is none in the data. The unusual intensity and chaos involved in this neural activity accounts for the sometimes erratic and strange content of dreams. Hobson also agued that the periodic activation of the brain during sleep is due to the giant cells of the pons firing in an uncontrolled way. This continues until the supply of the neurotransmitter acetycholine ,which they are sensitive to, is depleted. This brings about the end of REM sleep, until acetycholine stores are replaced, and the nest period of REM sleep will begin. CRICK MITCHISON 1983 Nuero Reverse Learning Theory of Dreams They argued that we dream in order to forget. They view the random firing during REM as the brains method of destroying synaptic connections involved in storing useless information. The removal of worthless or parasitic information creates space for material of more use. They called this process reverse learning or unlearning. 7 They point out that animals who do not have REM sleep, such as dolphins and spiny anteaters have abnormally large cortexes. This could be that they have developed in this way to house vast amounts of information. Alternatively, it could be that with the extra space they have no need to unlearn. Winson suggested that a large cortex enables them to carry out unlearning while awake. This theory would explain why we rarely remember our dreams. According to this model, to remember a dream means that we have re-stored the very info. We were trying to forget. This does not explain why some dreams are very coherent and significant. Connectionists theories suggest that we have no need to save space as we have vast potential for storage information. Critics of neurobiological theories argue that if dreams were meaningless, history would not have provided us with so many examples of creations and inspirations that have manifested during them. Neither the psychological or neurobiological theories of dreaming can account for the findings of activity very similar to REM sleep in foetuses. Jouvert suggests that the firing of nerve cells during REM activates information, concerning instinctual behaviour, that is stored in the genes. Once activated it is then programmed into the brain.