The following article may be of interest for the learning outcome the influence of hormones on behavior:
Gender bender
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Here is some interesting information that can be used for the learning outcome "the interaction between physiology and cognition in terms of a cognitive process" (in this case memory), but also for the effect of the environment on one physiological process (in this case brain plasticity).
A study by Lazar has shown that the brain grows new connections in the prefrontal cortex through meditation. The study also showed that it improved attention and memory. It may be argued that because the person is improving his attention, also remembers more. How to get smarter, one breath at a time Another study by the University of Pennsylvania has shown that meditation may be a helpful technique for patients suffering from Alzheimer's disease. It is even possible that mediation may reverse memory loss. One possible reason for the effectiveness of meditation on memory is because it reduces stress, and stress impairs our memory through stress hormones that kill brain cells. By reducing the release of stress hormones you are also improving your brain functioning. Cerebral blood flow in subjects with memory loss: a preliminary study An easy meditation practice to reverse memory loss This is an interesting article on new research on the teenage brain:
What's wrong with the teenage mind? In this article, the author criticizes that we keep on adding hours for education when we actually should offer more apprenticeships for teenagers to be more prepared for adulthood (which, currently, they are not) Our culture may be the reason why so many young people are very knowledgeable but at the same time directionless. Another interesting finding is that teenagers care more for social rewards than adults, and that they overestimate rewards (winning and falling in love are creating stronger sensations in teenagers compared to adults) This is a new and interesting brain scan study that suggests that bilingualism may delay the onset of Alzheimer's disease:
Brain scans show bilingualism can delay Alzheimer's disease Information in this post may be useful for the learning outcome "The effect of social factors on cognitive processes". I have just read the book "IBrain. Surviving the technological alteration of the modern mind" and I will summarize some of its' key points here.
Because of the plasticity of the brain, our minds are being altered by the use of technology, such as computers and television. This may also be the case for other technologies, such as books and some researchers believe that tool use had a significant effect on the brain development of our ancestors. In summary, it can be said that computer may alter our attention span, our ability to multi-task, our self esteem, our intelligence, our memory, our aggression, our empathy and our social relationships. It can also lead to burn-out and addiction. Our intelligence may be improved by computer use. Small, Bookheimer and Moody conducted MRI scans on people conducting google search. It was a natural experiment where the researchers included those who were frequent internet users and those who did not use internet frequently. The researchers also included a control task where the participants were scanned while reading a book. The results showed that just after 5 hours the computer naive subjects had rewired the area of their brain called the dorsolateral prefrontal cortex. It is an area related to working memory and our our ability making decisions and integrating complex information. As a matter of fact, the average IQ scores are rising constantly every year. This is know as the Flynn effect. Our stress levels and our attention span can be affected by too much computer use. Linda Stone has coined the term continuos partial attention to describe the computer behavior of keeping track on everything but having a hard time focusing on anything (because of constant messaging and e-mailing). Being in this continuosly stressful alert state may eventually create techno burn out. The constant flow of the information on internet can also create stress. My blog is actually an example of how I try to keep track of every new information I can find related to psychology, and it is quite stressful. Computers may also increase our ability to multi-task. Multi-tasking allows for computer uses to get instant gratification, but it may also distract them, put them out of focus, create stress and make them work inefficiently. It is even suggested that technology such as television, video and computers contribute to the risk of attention deficit disorders (such as ADHD), especially if a person is exposed to the technology in early childhood. It is important to emphasize, however, that this research is mainly correlational, and it may also be that individuals with ADHD-like symptoms are more attracted to technology (because of its instant gratifications) than other individuals. In general, our attention and memory seem to diminish just while we are using computers. A personal example is that I find it harder to concentrate while reading a pdf file on a screen that reading the actual book or print-out. One research study showed that participants were more likely to remember information that was typed into a computer if they were told that the information would not be saved (as in comparison in that it would be saved) This is called the google effect; because we rely so much on search engines nowadays we often don't make an effort to remember information. Internet use can also have an effect on our self image and self esteem. I now remember a study that has correlated internet and facebook use and self esteem. People who use internet a lot tend to have lower self esteem and vice versa. Interestingly enough, the amount of pictures of yourself that you have on facebook is positively correlated with your self esteem. It can be assumed that the effect of internet on your self esteem can alter your brain. Lupien and colleagues have found that your self esteem is related to the size of your hippocampus. The bigger your ego, the larger your hippocampus. One danger of excessive computer use may be a diminished ability to read emotions and social signals of others. There is limited research on this, but the main argument behind this claim is that adolescence is an important period for the brain to develop empathic abilities, and if teenagers spend their most of their time alone with a computer, they miss vital time to develop social skills. There is a fear that obsession with technology delays social and reasoning abilities and impairs capacity to delay gratification (because computer games and multi media give constant and instant gratification) Interestingly enough, a psychological disorder that relates to social problems, autism, is also related to technology use. The more an individual is exposed to technology, the more likely he is to suffer from autism. As in the ADHD case, however, it may just be that technology attracts autistic individuals. There are also many types of psychological disorders that come out technology use, such as addiction to gaming, gambling, social networking, and online shopping. There are also psychological diseases that can be spread online through peer pressure or mass hysteria. Other psychological phenomena related to internet are online suicide clubs or internet suicides (where the suicide kills himself in public via the internet). Morgellons' disease is a disorder where the person believes that he has been infected by parasites through internet use. It is most likely a type of delusional parasitosis, where the sufferer has a false belief that he is infected by parasites and can feel them crawling under his skin. This is an interesting article related to localization of function and the plasticity of the brain.
Girl loses half her brain in a car crash and gains an artistic ability A truth serum is a drug that can be given during interrogation to obtain information from an individual. Of course there is no drug that can make people be completely honest, there are drugs that can make people delirious and talk a lot, mixing fantasy with reality. Truth serums are illegal in many countries, but many intelligence agencies use them. Many different types of drugs have been used as truth serums, including alcohol, LSD and Scopolamine. Why scopolamine should be successful as a truth serum, I don't know, because it actually inhibits the neurotransmitter acetylcholine, blocking your memory.
Some believe that our knowledge of oxytocin may be used for truth serums in the future. Oxytocin increases your attachment and trust of other people, so an intake of it may make you trust your interrogator (or perhaps fall in love with him). Here is an article on truth serums: Some believe truth serums will come back Here is a link to a podcast on fMRI and other neurological devices:
http://www.nature.com/neurosci/neuropod/index-2011-10-28.html The neuroscientist Dr Daniel Amen has looked at 66.000 brain scans to identify the four different brain types of eating behavior which may be the case why different diets work for different people.
The first brain type of eaters is the compulsive type, who has a compulsion to eat and think about food. These tend to have a high activitiy in the anterior cingulate cortex, an area related to shifting attention and adapt to change. The second brain type of eaters is the impulsive type. These eaters have low activity in the prefrontal cortex, which is related to judgment, decision making and planning. Alcohol lowers the activity in the prefrontal cortex and low levels of dopamine are equally related to poor decision making. The third brain type of eaters is the emotional type. These eaters suffer from emotional problems, and eat in order to feel better. They have heightened activity in the limbic system and decreased activity in the limbic system. The fourth brain type of eaters is the anxious type. Anxious eaters eat because they are stressed or anxious. Anxious eaters have heightened activity in the basal ganglia, which sets anxiety levels. Carbohydrates (for instance sugar) have shown to activate the basal ganglia, releasing dopamine, which may explain the addiction that may come from anxiety. Here is the original article where you can also find out which type you are. I think I am a mix of all types: http://www.iol.co.za/lifestyle/successful-dieting-is-all-in-the-brain-1.1169858 I have recently read a little bit on genetics and behavior. Here I will share some of the new things I have found out.
1. Genetic drift. This I have actually known for quite some time, but natural selection and mutation are not the only ways in which evolution occurs. There is also sexual selection and a phenomenon called genetic drift. Because individuals have two copies of each gene, and pass one on their offspring randomly, chance variations of inheritance can make one genetic variant more common than another, even without any occurence of natural selection. This is more likely to occur in initially small populations. Therefore, it is important to be aware of that not every trait in humans have had an evolutionary advantage but just be a random occurence. 2. Gattaca. The name of the movie Gattaca, about a dystopian eugenics society, derives from the four bases of the DNA molecule; A, T, G and C. 3. On the genetic similarity between humans and other mammals. Rarely does evolution drop genes or create entirely new ones, and is for this reason that mammals have comparable gene counts. However, as evolution progresses, some genes can start working together or acquire slight mutations to perform new functions. It is also believed that the so called "junk DNA", DNA that does not code for any proteins, actually do have functions. It is for this reason that humans and other apes may be very similar in regards to their genome, but very different in abilities. 4. Genes and behavior. There are many example of the relationship between genes and behavior. People with defective FOXP2 genes suffer from language impairment, defects in the APOE gene is related to Alzheimers' disease, the IGF2R gene is related to intelligence, and the ASPM gene (a gene related to brain growth) is related to abilities for tonal language. Some research has also suggested that certain genes for depression are more likely to be found on the X sex chromosome, making women more prone for this illness than men. 5. Atavism and social darwinism. Atavism is the tendency to revert to traits of ancestors. The social darwinists believed that inferior races displayed atavistic traits and the criminologist Cesare Lombroso claimed that the traits of criminals were atavistic. Their theories have since long been discredited. 6. The selfish gene. The term the "selfish gene" was coined by Richard Dawkins and is a bit misleading. Genes have a tendency to replicate themselves. Through evolution, there has evolved "survival machines" to help genes for that purpose. That is us, animals and plants. What Dawkins means is that we humans are by-products of our genes tendency to replicate themselves. 7. Nature via nurture. As most research suggest that the heritability quotient for most behaviors and personality is between 0.3 and 0.7, it can be assumed that abilities develop through a combination of nature and nurture. For instance, if an individual has inherited genes that makes him physically strong, he may be more likely to enjoy and pursue sports. Similarly, if inherited genes give him an advantage to learn language and music, he may be more inclined for those behaviors. Nature and nurture are equally important for a behavior to develop. Caspi (his first name is Avshalom) and Moffitt have followed a cohort of New Zealand children born in Dunedin in 1972-1973, recording details of their life experiences and testing their DNA. Their findings suggest that individuals may be more at risk to develop certain disorders, but only if there is negative environmental influence. For instance, individuals with a short allele on the 5HTT gene for instance are more likely to develop depression, individuals with a variant of the MAOA gene are more likely to behave antisocially, and a version of the gene COMT increases the risk for Schizophrenia. However, the risk only increased if they had been maltreated as children, had experienced stressful life events or had smoked cannabis as teenagers. 8. One or more genes for behavior? For some rare diseases (such as Huntingson's disease), the cause may be the mutation on one single gene, but for most behaviors there is a plethora of genes interacting. Autism, for example, has been shown to be highly heritable, yet no gene that predispose to this developmental disorder has been found. This suggests either that the development of the disease comes from a multitude of genetic variants or from spontaneous mutations unique to certain families. In most cases, single genes contribute only to slight influences of certain behaviors. 9. Homosexuality and heredity. The Xq28 gene has been linked to homosexuality. Research by Camperio-Ciani (2004) has also suggested that genes that dispose for homosexuality also dispose for high fertility in women (this is why homosexuality does not disappear through natural selection). Female relatives to homosexuals were significantly more fertile than female relatives to heterosexuals. It is also suggested that exposure to high levels of testosterone in the womb may increase chances of homosexuality. Both gay men and women tend to have long ring fingers, which suggests high levels of testosterone in the womb. 10. The genome and medicine. As only twins' genome look exactly the same, drugs can have different effects and side effects on different people. Therefore, doctors and patients usually have to use trial and error to find what works for a patient for a particular drug, such as SSRI:s or antipsychotic medicine (Clorazine has shown to have bad side effects on men with Afro-Caribbean origin). I also know from before that antidepressants have different effects on men and women. 11. Epigenetics. Research has demonstrated that the experiences of your grandparents or earlier generations can have an effect on your genome, switching genes off or adjusting their activity. Child abuse can also create epigenetic effects. Szyf investigated the brains of men who had commited suicide and been abused as children. They had normal genetic sequencing but their epigenetic programming were different from thos that had died from natural causes. 12. Ethical issues of genetics. There are several ethical issues with genetics. One problem is discrimination, for instance its' influence on insurance. For instance, a study has shown that people who have discovered that they have a gene that increases their risk for Alzheimers' disease are more likely to buy insurance to cover long-term nursing care. This may discriminate against other insurance holders, who must pay higher premiums as a result. Those with a proneness for certain diseases may also be discriminated by insurance companies. This is already true for those have a parent with Huntington's disease and insurers often ask about family history before allowing insurance (or raise premiums if the person is at risk for a certain disease). Another ethical issue is genetic determinism. In 1991, Stephen Mobley murdered a man. His lawyers demonstrated that his family had a long history of violent criminals and that he carried a mutation to the MAOA gene that is linked to criminal behavior. Even though the gene does not inevitably lead to crime, it may contribute to it. Some has therefore suggested that research like this can assist in determining degrees of accountability, in a similar fashion to what psychiatric illness does. |
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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