Further evidence to question the hypothesis comes from research by Rittenhouse et al. (1994) who found that, most of the time, dreams were meaningful and coherent. He studied over 200 dreams and found that only 34% had discontinuities i.e. things that didn’t make sense. This means that the majority of dreams were not random or meaningless. This contradicts the view of the activation-synthesis hypothesis, which suggests that dreams are just the result of random signals being sent from the brainstem. If this were the case, then surely we would never have the same dream twice or be able to understand our dreams but many people have repeated dreams and are easily able to recognise meanings in them. This, again, causes us to question how much we can use the activation-synthesis hypothesis to explain dreams.
However, when assessing the dreams that were considered not random or meaningless, it may be that the participants’ brains were simply doing what Hobson and McCarley suggested and making sense of randomness. The dream might have actually been nothing like what they remember it to be and they simply altered their memory to fit what they can understand. This suggests that we cannot tell how valid Rittenhouse’s research is. Participants may have also acted in ways they believe corresponded to what the researcher was looking for. Thus, the participant may not have reported their dreams in an accurate way and therefore we cannot be sure that the findings were not affected by participant bias and so may not be useful in our explanation of dreaming.
On the other hand, Foulkes also criticised the activation-synthesis hypothesis. He found that dreaming is absent in children till around the age of 3-5yrs and does not assume the form of adult dreaming until about 7. Children do, however, have REM activity, which cannot be explained by the hypothesis.
However, this may be due to the fact that children have difficulty describing dreams and so it is difficult for the researchers to tell whether they have dreams or not. This causes us to question how valid this research is and therefore means that we may not be able to use it in our attempt to explain dreams.
Following criticism of the hypothesis, Hobson (1998) developed the AIM (Activation, Inputs and Modulators) model. Inputs is referring to the external and internal stimuli and Modulators is referring to the neurotransmitters involved, serotonin and acetylcholine. It describes awake, NREM and REM as variations of A+I+M. When you’re awake you have high activation, high external input and high serotonin. When in NREM sleep you have medium levels on all three variables and when in REM sleep you have high activation, high internal input and high acetylcholine.
This was an advance from the previous 2 dimensional models such as traditional sleep graphs. It proved to be more useful in sleep and dreaming research because all 3 dimensions, A, I and M are entirely measurable which gives it high internal validity. However, Morrison and Sanford suggest that any model used in research is premature because we simply do not know enough about the brain. One could argue that the AIM model is an evolving one and will change with time when the technological development allows it. Overall it seems that Hobson’s neurobiological theories have made a substantial and valuable contribution to the explanation of dreaming.
b) Outline and evaluate one psychological theory of dreaming
Freud saw dreams as primary-process thought (repression). He believed that personality consists of three fundamental structures: the id, the ego and the superego. The id is the most significant idea in Freud’s theory of dreaming. This is the unconscious foundation of our desires and the source of fantasies deriving from these. The id is associated with irrational, instinct driven, unconscious thought called primary-process thought. This form of thought is often seen as controversial to the adult conscious mind so is shifted to a person’s dreams. Freud called this repression. In our dreams, we can act out our wishes and desires without suffering the consequences. Freud believed that if we did not do this regularly, then our sanity would be severely threatened by a build-up of energy invested in these unwanted desires. Thus he saw dreams as a form of protection by allowing people to express these latent urges in a passive way.
According to Freud, although dreams represent unfulfilled wishes, their contents are expressed symbolically. The real meaning of a dream (the latent content) is transformed into a more harmless form (the manifest content), which may appear random and meaningless to anybody but a psychoanalyst trained to understand these symbols. Freud believed that, in order to understand the symbols accurately, they need to be considered in the correct context of a person’s life. He also sometimes believed that there was no hidden meaning and that sometimes a dream was not symbolic at all.
However, this theory is unfalsifiable. This means that it is difficult to prove wrong. We have no way of telling whether Freud’s theory is correct or not. If someone, such as a patient, rejected his interpretation of their dream then he would say that it was simply a sign of repression and that it only further supports his interpretation.
One could also argue that his theory was culturally biased. He often based his theories on his own case studies of his patients who, more often than not, were self-conscious, irrational, Viennese women. This is unlikely to be a fair representation of the average population, which may mean that we cannot generalise it to anyone else other than those who fit this specific criteria.
A further criticism is that it lacks research support. Unlike the neurobiological theories, which were supported by PET and EEG scans, Freud had very little to back it up. In terms of his theory, it is the ego that is seen as inactive during REM sleep and the id that is very much still active. This explains why dreams are filled with strange images. But there is little evidence to support these ideas. If we were to compare this to the neurobiological theories, we could suggest that the ego could be represented by the prefrontal cortex that is inactive during REM and the id could be represented by the frontal lobe that is concerned with emotion and memory that has been shown to be active during REM. This would support Freud’s theory if we were to relate it to these modern interpretations.
The same research by Solms (2000) can be used here also, as he suggested that dreams are activated by the forebrain and not by the brainstem.
However, Braun (1999) suggests that we cannot explain the processing that is taking place to transform latent content into manifest content because this is surely done by the rational, thinking part of the brain, which is, according to Freud, not active during REM sleep. This causes us to question how valid Freud’s theory can really be as it appears to contradict itself. This may lessen the extent to which we can use this research in our explanation of dreams.
A further criticism of Freud’s ideas is that not all dreams are easy to see as wish fulfilments. Nightmares, for example, are hard to explain using the idea of dreams being realization of our unspoken desires. This causes us to question Freud’s theory. It lowers the face validity of his ideas because we cannot see how nightmares would fit into his explanation.
A better explanation of dreaming may be Cartwright’s theory of dreams as problem solving. This would explain why we have nightmares when we need to solve emotional problems that we may be experiencing during the day. Dreams are a place where we can reflect on our major emotional concerns and confront any conflicts that we may be having in our conscious life. This way, a person can work through their issues that were troubling them before. As a result, they may feel they can cope better with everyday life. This theory has high face validity than that of Freud’s idea because we feel we can apply it to a wider variety of dreams.
Overall, it seems that whilst Freud’s theory may have been held back by the lack of technological capabilities, it does seem to bear similarities with some of the 21st century ideas of dreaming. The only difference appears to be the labels and connotations that we give the areas of the brain. It is possible that Freud was correct in some of his assumptions and this can be supported by modern day research. However, it has also been criticised for it’s lack of contemporary support and it’s inability to explain a wider area of dreams to the point where we become unsure of the extent that we can find it useful in our research on the explanations of dreaming.