A student recently reminded me of the power nap, which is a 15-30 minute nap which is claimed to increase alertness significantly. Combined with caffeine intake (caffeine nap) it gives the best effect, because the effect of caffeine takes more than 15 minutes and thus does not interfere with the nap. Caffeine, by the way inhibits adenosine receptors in the brain, which in turn increases the activity of dopamine and glutamate. Glutamate is important for learning and memory, whereas the increased dopamine activity can explain the pleasure (and potential addiction) that comes from drinking coffee.
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We know that brain functions that are trained will develop, whereas those that are less used may be impaired or fade away. I speculate that some brain functions may be impossible to develop at the same level, partly because the processes may disturb each other, and partly because they may utilize the same areas of the brain.
As the brain processes information in parallell, I conjecture that different processes can interfere with each other. Because of learning and disposition, some brain processes may be more dominant and inhibit other processes. In most people, for instance, the left brain hemisphere's processes is more dominant than the right brain hemisphere's processes. This dominance of some brain processes over others may also be seen in cases of addiction, where the dopamine system is "hi-jacked" by the craving for a certain drug or activity so that nothing else matters. Obsessions or compulsions are similar to addiction in the way that a certain idea or behavior dominates a person's thinking or behavior. It also makes sense that inner attention (conscious thinking) will inhibit a person's body movements. For instance, if you think too much while playing sports, you will underperform. It is possible, that in order for some brain processes to be highly active, others need to be inhibited. This may explain why some highly intelligent people have had obvious problem making good decisions or have had problems in their social life. For instance, the economist Keynes had personal financial problems and it is suggested that the philosopher Plato was poor at playing the macchiavellian game of politics of his time (even though he knew a lot on politics). Savants are other examples; these are individuals with developmental disability who are highly talented in one area but have high impairment in other areas, usually for social and communicative skills. The brain system deciding which brain processes to inhibit and which to increase may be the executive functions. The executive functions are the common name for our attention, ability to multi-task, make decisions and monitor our own actions. In other words, it is our "free will". The executive system utilizes working memory to perform its' actions and it is usually what we refer to when we speak of consciousness. Damage to the executive functions can lead to poor decision making. It has been suggested that individuals with the ADHD syndrome have impaired executive functions. It is essential that the executive functions inhibit some brain processes and increase others while we are making decisions, otherwise we may be filled with a lot of doubt for any action we do or act paradoxically. We all know that it is impossible to both eat a cake and have it; once we have made a decision (or even before) we need to persuade ourselves that the action we are undertaking is the best option. We cannot be two-faced for long because of the cognitive conflict it will cause (compare with cognitive dissonance theory). Soon we will have to harmonize our thoughts, perhaps through an obsession. Psychoanalytic theory, however, suggests that repressed cognitive processes (ideas) may constantly struggle to find ways of being expressed. If this is true, inhibition of a brain process does not not necessarily have to mean the extinction of it. One theory is that humans evolved because of our complex social groups. Humans are particularly complex because of our strong learning capacity (our adaptibility and learning ability may well me our finest adaptation) which make us very different from each other. Because of our individual differences, it is very difficult to tell what we can expect from someone, his abilities, whether he can be trusted or not and whether he will return favors. In short, because of our learning capacity we became very different from each other. In order to make a group of individuals function well there was a demand for even greater brain power.
It is fairly established that many functions are localized in the brain. However, for a healthy brain those functions are strongly connected and work as a whole. These strong interrelations between the different areas of the brain is called connectivity. The higher and lower centres of the brain have strong connectivity and usually work together for different functions (for instance, the amygdala and the frontal cortex in regards to emotion)
The higher centres of the brain can be found in the cortex and are related to consciousness and volitional behavior. The higher centres always work together with the lower centres of the brain (such as the limbic system - which initially was evolved for smell), which are more automatic and nonconscious. Well trained actions have a tendency to become automatic/nonconscious (which can explain the Stroop effect). The processing of the higher centres of the brain is always a bit slower than the lower centres of the brain. It has even been claimed that our awareness migh lag 25 milliseconds behind events in the real world (see Libet's research). It is possible that the development of culture and literacy have led to a stronger division between the higher and lower centres of the brain and our experience of a distinction between mind and body. One example of the brain's strong connectivity is memory. Different memory functions are located in different areas of the brain and as with other functions, such as consciousness, these areas work together when performing the function. The hippocampus is believed to be important for spatial memory and consolidation of memory. The rhinal cortex, which is next to the limbic system, is believed to be very important for explicit and declarative memory. Attention is a mental process that can be directed either inwards (through imagination) or outwards and is a combination of bottom-up and top down processing. Whether a person is thinking or is focused can easily be spotted through his gaze. If he is attentive on his environment his gaze will be more fixated. Vision involves about 40 percent of our brain and thus more than the occipital lobes. What is interesting is that there is conscious vision and unconscious vision, as demonstrated in the peculiar blindsight disorder. People with blindsight have had their visual area V1 damaged and report seeing nothing. However, when performing visual tasks they are able to make correct guesses or judgment in most of the cases. If there are disturbances in the brain, such as chemical malfunctions, abnormal firing of neurons, our experience of a unified self or consciousness may break down. We may hallucinate, develop delusional thoughts, or hear voices, because we fail to distinguish between our inner imagination and outer reality, or our own inner (or outer) voice as belonging to ourselves. This is a new documentary series by BBC on the brain. Here are youtube links to the six episodes:
BBC Brain Story - All in the Mind BBC Brain Story - Growing the Mind BBC Brain Story - The final mystery BBC Brain Story - First among equals BBC Brain Story - The Mind's eye BBC Brain Story - In the heat of the moment Akinetopsia, or motion blindness is a rare neurological disease in which the patient cannot perceive motion. He or she can see stationary objects without issue but the world is devoid of motion. Most of what is known about of akinetopsia comes from the case study of LM. Patients with Alzheimers disease may also have varying degrees of akinetopsia.
LM has reported having trouble pouring a cup of tea or coffee, because the fluid appears to be frozen and she does not know when to stop pouring because she does not see the fluid rising. It is also difficult for her to follow conversations, because she cannot see lip movement or change in facial expressions. She also gets nervous when people are walking around in the room because she never sees them move and therefore suddenly sees them at another place of the room. In addition, it is difficult for her to cross a street, because she cannot estimate the speed of cars. However, she can still hear well and can use her hearing to estimate distance. Research has shown a connection between the length of the ring finger and testosterone. Men tend to have a longer ring finger in relation to the index finger in comparison with women. This is because sex hormones affect fetus development. Interestingly enough, research suggest that men with longer ring fingers in relation to the index finger tend to have more masculine traits. For instance, such men are more competitive (for instance, in regards to sports) and risk taking (for instance, in regards to trading). So in this case, it seems that length matters...
Deception, making people believe things that aren't true is a fairly well understood behavior. But what about self deception? Is it really possible to deceive oneself? Self deception is a controversy for philosophers and psychologists alike, as it challenges the common view of the self. Some even claim that self deception is impossible.
In real life, however, we see behavior that may best be explained by self deception. In this world there seems to be many who refuse to face the truth and reality for various reasons. A common psychological explanation of self deception is freudian. According to Freudian theory, uncomfortable and anxiety provoking thoughts can either be denied, repressed or rationalized. In addition, Freud distinguishes between wishes and thoughts. It can be argued that because we want to and have a need in believing in something we sometimes confuse reality with our desires. Freudian theory also distinguishes between the conscious and unconscious self, which opens up for the possibility that our unconscious self can "deceive" our conscious self and vice versa. According to cognitive dissonance theory, two conflicting ideas creates mental anxiety and discomfort. We therefore have a tendency to either repress one of those thoughts or rationalizing our behavior or ideas to such an extent that we can harmonize the conflicting ideas. For instance, if you want to smoke but know it is bad, you may claim that you are only a party smoker (you may however often go to parties and therefore smoke a lot) There is also an evolutionary explanation of self deception. Trivers (the same researcher that developed the altruistic theory of self reciprocity) believes that self deception is a behavior that has evolved in order to be able to deceive others. If you truly believe in a lie that you are telling someone else, it is best to believe in it yourself. Then it won't show in your body language that you are lying. Girls prefer to play with dolls and boys with cars very early on in life. One British study showed this bias existed when children were between one and three years old.
Boys prefer cars very early on Socialisation is of course important, but I also know of another study, where girls that were born with an overproduction of testosterone also were more likely to prefer to play with cars compared with girls with normal levels of testosterone. An explanation put forward by one of the recent researchers is evolutionary. Girls prefer to play with dolls because they have a nurturing tendency. The reason why they prefer pink is because it is the usual color of a newborn baby (a bit far-fetched, don´t you think). Boys prefer moving objects because they have a hunting instinct. As usual this is only a hypothesis. Have I ever told you that teenagers brains differ from adult brains? It is believed that the brain is not fully mature until the age of 25, especially in the frontal cortex. This make it more difficult for young people to plan ahead, to make rational decisions, and keep their focus.
I am a bit skeptical about this type of research, because I know that many teenagers can be very mature, as there can be adults over 25 that can be very immature. However, there are differences in brain anatomy between adults and teenagers. One difference is that teenagers have more grey matter than adults. It is in the grey matter where most of the brain processing takes place. It is not always best to have too much grey matter, because it means that there can be many confusing and unnecessary connections between neurons, which slows down the processing. Adults have less grey matter because their neurons have learned which connections that are important. Unnecessary neural pathways have been shut down. It is my speculation that this may be the reason why adults often are more effective at many tasks than the younger generation but on the other hand may be more conservative and less open for new ideas. Young people are on the other hand more liberal and open for new ideas, but their oversized grey matter may make them unfocused and slow during information processing. On the other hand, if one has more grey matter, one also has potential for great ability. One only has to learn to use it wisely. Here is a documentary by PBS on the teenage brain: Inside the teenage brain |
AuthorThis is my class blog for IB Psychology. Here I will publish reflections on psychology, reviews of psychology books, recommended links, lecture notes, and information on psychology topics that are not covered by the syllabus. You are free to add comments or ask me questions. Archives
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