If you explain how PET scans work, it is good to use examples of real PET scan studies. One PET scan study that can be used to explain the effect of Alzheimer´s disease on memory (the learning outcome "The effect of biological factors on one cognitive process") is a recent study by Wong (2010). The study demonstrates a new PET scan technique to diagnose Alzheimer´s disease. They injected a radioactive tracer substance (florbetapir F 18). Florbetapir mainly binds to the brain areas that are affected by Alzheimer´s disease, making it possible to spot them through a PET scan. This may increase the reliability of diagnosing patients with Alzheimer´s disease and make it possible to diagnose patients with Alzheimer´s disease when the disease is in its´early stages.
PET agent unlocks door to Alzheimer's disease
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The information in this article may be used when explaining the principle of how the physiology and anatomy of the nervous system affects our behavior or the effect of neurotransmission on behavior. Here I will present a simplified view of how our brain affects behavior. Our brain consists of billions of neurons, connected in a complex network. The brain does does not have any central system, instead there are many interacting systems in this network. This parallel processing of the brain is different from the serial processing of most computers (however, the left brain hemisphere process information more serially than the right brain hemisphere). The brain and body also interact with the environment. In addition, information from our senses can trigger memories and influence behavior.
The interacting systems of the brain can sometimes work together, and sometimes work against each other. Sometimes, supposedly, we can have conflicting impulses, which may cause indecisiveness. For example, the sight of a cookie may trigger an impulse to eat the cookie, but the decision making processes in the frontal lobe may suppress this impulse because we are thinking of our weight. In order to understand how the brain can either suppress or activate certain behavioral tendencies, one should be aware of that neurons can either transmit or not transmit electrical impulses, but whether they do depend on the neurotransmission in the synapses. Different types of neurotransmitters, produced in different regions of the brain, can either excite or inhibit the activity of neurons. They do so by affecting different types of receptors in the neurons. Therefore, the neurotransmitters in the brain can excite or inhibit systems of the brain, which in turn will have an affect on our behavior. In one particular situation, some processes may be inhibited, whereas others are excited, which will produce a certain behavioral output. In the cookie example, the neurons that control our desire to eat the cookie were inhibited whereas the neurons that control our conscience were excited. GABA is the most common inhibitory neurotransmitter in the brain. This amino acid is found naturally in brown rice, and has a calming effect on the body. The major excitatory neurotransmitter in the brain is Glutamate, which is important for memory processes. As you know, there are also many other neurotransmitters. One example is Acetylcholine, which is related to learning, memory and movement. Another example is Dopamine, which is related to fine motor movement and pleasure. The effect of nerve gas demonstrates the importance of neurotransmission for behavior. Nerve gas destroys the synapses, preventing them from sending signals, so that the body and brain lose their functioning. The same is the case with the arrow poison Curare, which is used by the South American Natives. Curare paralyzes its victims, mainly because the chemical blocks the ability of the neurons to receive Acetylcholine. Besides Acetylcholine, Dopamine is also important for motor movement. Patients suffering from Parkinson´s disease, which primarily affects body movement, have an underproduction of Dopamine. In the 1960s, the neurologist Oliver Sachs managed to wake up a group of patients suffering from the Parkinson related disorder Encephalitis Lethargica (also called "sleepy sickness") by giving them L-Dopa. L-Dopa is a medicine that stimulates Dopamine production in the brain. After decades of sleep, these patients woke up from their catatonic state, trying to deal with a new life in a new time. However, after only a few weeks, they developed a tolerance to the drug, relapsing into their catatonic state. This true story has been dramatized in the movie Awakenings with Robin Williams and Roberto De Niro. Drugs can influence our behavior just because they influence neurotransmission. Drugs enter your bloodstream and are small enough to cross the blood-brain barrier. Because drugs imitate natural drug chemicals they bind to the same receptors and can therefore alter our consciousness. Alcohol prolongs the effect of GABA in the synapse, making us more relaxed. Cocaine blocks the reuptake of Dopamine of the presynaptic, increasing the effect of the transmitter (pleasure). Caffeine reduces the production of GABA, making us more aroused. Here are some animations on how neurotransmission works along with how drugs affect neurotransmission, should you be interested. Animation on how neurotransmission works Animations on how drugs affect neurotransmission It has sometimes been claimed that the biological view of behavior is deterministic and threatens our notion of free will. A number of studies that are challenging the notion of a conscious free will were conducted by Libet in the 1980s. Participants were seated in front of a computer screen with a moving dot. They were asked to carry out a simple action within a certain time frame. When they did it was voluntary. They were told to state where exactly the dot on the screen was when they consciously decided to take the action. Their motor movement in the hand and the brain activity was measured by EEG. Results demonstrated that the neurons in the hand and brain were activated before they had consciously decided to take the action (when they consciously decided to take the action could be estimated by the position of the dot on the screen). This study may challenge our view that free will is conscious. It may, however, still be unconscious. Other studies have challenged Libet´s assumption. In one study, patients undergoing awake brain surgery were electrically stimulated areas in the parietal region. Stimulating the areas triggered a strong intention and desire of the subject to move his limbs or talk. If stimulation intensity was increased, participants thought they had performed the movement. If the researchers stimulated some areas of the motor region which led to mouth or limb movement, patients denied that they had moved. This study and others suggest that conscious intention arises before movement, and that the intention process for motor movement can be found in the parietal lobe. Therefore, whether we have free will or not is still a question of debate. I recently read an article on the brain and memory. The information from it may be used if you choose to discuss the interaction between physiology and cognition in terms of one behavior (amnesia) or biological factors of one cognitive process (e.g., the effect of Alzheimers disease on memory), and the effect of neurotransmission on behavior (e.g. the effect of glutamate on memory)
I want you to know that the hippocampus is not the only area of the brain that is involved in memory, even though it is important. After a stimulus is made conscious by processes in the frontal lobe the potential memory is transferred to the medial temporal lobe. The medial temporal lobe is where the short term memory is situated in the brain. Inside the medial temporal lobe is the hippocampus. Researchers do not yet agree on the role of the hippocampus for memory. Some believe that it serves as a temporary store before the memory is being transferred to long term memory, others believe that it plays an active role during the development of new memories, by forming associations of the memory to words, pictures, smells and sounds. The amygdala, which is adjacent to the hippocampus, create associations of the memory to emotions (the schematic processes of the brain may therefore be located in the hippocampus and amygdala). The memories are then stored in all areas of the cerebral cortex (the outer layer of the forebrain), but mainly in the parietal lobe (this brain area can be found under the top of your head). Therefore, your short term/working memory can be viewed as being located in your prefrontal lobe, and your long term memory in your cortex. The hippocampus is the mediator between long term and short term memory, the one that is forming the associations of the memory. Here is a map of the anatomy of the brain if you want to understand my explanation visually. It is also interesting that remembering and simulating the future activate the same brain regions (that is, the inner temporal lobe with the hippocampus, the frontal lobe and the parietal lobe) This is further support for the reconstructive nature of memory. When we are recollecting a memory, our brain is simulating the experience in the same way as we are imagining our future. How memories are physically stored in the brain is poorly understood, but it is widely assumed that the storage depends on biochemical alterations in the synapses. The storage depends on a brain process called long term potentiation (LTP). If a group of neurons are stimulated repeatedly by an experience, they become more sensitive to later stimulation. This is because the stimulated neurons have added new receptors, and thus increased their sensititivity to neurotransmission. There are many neurotransmitters involved in learning and memory processes, one of which is acetylcholine. For LTP, however, a neurotransmittor called glutamate is important. When glutamate continues to bind to the so called NMDA receptors in the brain, chemical processes lead to a production of a protein called CREB. The CREB protein activates a number of genes in the DNA, which in turn creates proteins to form the new receptors. I find it fascinating that not only neurotransmitters and neurons are involved in memory storage, but also genes. In the same Swedish magazine on biology and memory, there was also an article on Alzheimer´s disease. Alzheimer´s disease is partly genetic. Half of all patients with Alzheimer´s disease have a gene for Apoliprotein-E4 on chromosome 19. This mutation can make the neurons produce too much of the beta amyloid protein. These proteins may create plaque deposits that eventually destroy the neurons. At the same time the Tau protein in the neurons form tangles, also destroying the neurons. The cause of these tangles is currently unknown. The tangles and the plaques usually build up in the parietal lobe (important for long term memory) and then later move to the Hippocampus. The tangles and the plaques primarily attack those neurons that produce the neurotransmitter Acetylcholine. Finally, neurons in the frontal lobe are destroyed, an area important for personality, thinking, and language. I just read an interesting Swedish article on brain scanning. This is what it said about PET, MRI and fMRI
The PET scan technique was developed in 1962. With this technique a radioactive substance is injected into the bloodstream. The most commonly used radioactive substance is the sugar fluorodeoxyglucose (FDG), often labeled fluorine-18. A scanner can show the activity of different brain areas because the active areas will use more of the blood flow. The blood flow to the different brain areas can be measured by the radioactive decay of the substance. A computer constructs an image of the brain activity based on the data from the gamma decay. One weakness of the PET scan is that the measures must be done shortly after the injection (about one hour), because the radioactive decay goes very fast. The amount of radiation absorbed by the body from the radioactive substance is relatively low, but can be dangerous to individuals who are sensitive to radiation. Women who are pregnant or breast feeding should avoid PET scans. There is also small risk for allergic reactions to the tracer substance. The MRI scan technique was developed in 1972. An MRI machine creates a powerful magnetic field around the subject´s brain. Because of the magnetic field, the magnetic moments of the hydrogen atoms in the brain align with the direction of the field (because of the abundance of water in the body and brain, MRI scans usually focus on hydrogen atoms). After the magnetic moments of the hydrogen atoms have aligned with the field, an electromagnetic field is briefly turned on. The electromagnetic impulse pushes the atoms back to their original state. This change produces radio waves which are detected by a scanner. A computer registers the radio waves and estimates the location of each atom, creating images of sections of the brain. Because an MRI scanner creates a very strong magnetic field (approximately 10.000-40.000 stronger than the earth´s magnetic field) the subject cannot have any metallic objects in or on their body (e.g. pacemaker, implants, screws) while being investigated. fMRI is a development of the MRI technique and focuses on oxygen atoms, which are abundant in the blood stream. More oxygen atoms will be present in active areas of the brain. Because of this fMRI can measure the activity in different areas of the brain (unlike MRI that can only show brain structure). During MRI scanning, tracer substances are often injected. Unlike PET scans tracers, they are not radioactive. They may however cause an allergic reaction or . Earlier this week I realized that there is a difference between being creative and being imaginative. I realized this because I am fairly unimaginative but consider myself to be fairly creative. Imagination is the ability to imagine pictures, sounds, smells, locations, scenes etcetera whereas creativity is to think out novel ways to improve things. Both abilities can be trained and combined they can create an optimal effect. Here are two other blog authors with similar ideas as me:
Imagination versus creativity What does imagination have to do with creativity About three years ago a student asked me if she could write an extended essay on obsessions. I did not let her do it, because I did not think there was enough research to review. I do however think it is an interesting topic.
You might have heard the expression that someone has a "fixed idea". An idée fixe was the earlier psychological description of delusion. In the 19th century, the idée fixe was fashionable, so to speak. Monomania was a psychological disorder based on the concept. The person suffering from it was normal in all aspects except being obsessed with one idea or belief. Characters in literature often have an idée fixe. Monomania is no longer considered to be a psychological disorder (another example of the sociocultural criterion of abnormality), perhaps because it is all too normal for people to have fixed ideas. A person with fixed ideas is very similar to someone who is a fanatic. Delusions are a type of fixed ideas that are false. Their occurrence can partly be explained by schema theory. The belief dominates mental activity and is difficult to modify despite contrary evidence or rational refutation. People with anorexia nervosa suffer from the fixed idea of staying thin. A fixed idea can sometimes turn into a mania; which is an intense enthusiasm, interest, or desire for the idea. People with bipolar disorder often have fixed ideas during their manic episodes. There is currently no research on it, but it is possible that people with bipolar disorder often also suffer from anorexia nervosa. Obsessions are different from delusions. People with obsessive compulsive disorder (OCD - an anxiety disorder) tend to have uncontrollable thoughts, ideas or images. These thoughts are unpleasant and create anxiety in the individual. People who suffer from depression are more likely to suffer from obsessions, which have a negative effect on their self esteem. One common type of obsessive thoughts in those suffering from depression are thoughts of suicide. OCD is particularly common in women with postpartum depression (depression after childbirth) I distinguish between obsessions and fixed ideas/delusions, because the former often creates anxiety whereas the the latter does not necessarily have to be frightening. People with anorexia nervosa can however also have obsessions; they often suffer from OCD at the same time. One type of obsession may be their irrational fear of gaining weight. Another difference between an obsession and a fixed idea is that fixed ideas usually are delusions whereas people with obsessions usually recognize the absurdity of their thoughts, even though they are unable to control them. A third difference between obsessions and delusions is that obsessive people are unlikely to act on obsessions that can be dangerous to others or themselves. People are however more likely to act on delusions, because of the positive feeling they may generate. Why do we have obsessions? From a biological perspective, obsessions seem to be related to an imbalance in the serotonin system, which is the reason why OCD is often treated with the help of antidepressants. Studies also show that for OCD patients, the brain is overactive in the prefrontal lobe and the caudatus nucleus. The caudatus nucleus connects with the thalamus, hippocampus and indirectly the amygdala. These areas are important for our fear and alarm responses. It is likely that symptoms of OCD depend on inaccurate alarm signals from these brain regions. From a cognitive perspective, we are suffering from from obsessions because we pay attention to them. However, if we try to suppress these thought they tend to become stronger. Because these obsessions create certain urges, the mind learns to control the obsessions with certain rituals or compulsions. Because anxiety is reduced by these compulsions we may become conditioned to repeat these compulsions over and over again. Delusions, on the other hand, are related to dopamine and the brain´s reward system. One PET scan study has found that patients suffering from anorexia nervosa have overactive dopamine receptors in one area of the brain. Cognitive dissonance theory may also explain delusions. According to this theory, conflicting ideas create negative emotion. We are therefore motivated to create a consistency in our thought patterns. This can lead to confirmation bias, rationalization and all sorts of cognitive biases. Now I am speculating, but it is possible that delusional behavior is compensation for negative thoughts about oneself. It is by being lost in one fixed idea that we can prevent ourselves of dealing with reality and deny our personal problems. Which may also be the reason why people with bipolar disorder often can go from a manic episode to a depressive episode. When the delusion disappears, the obsession takes over. Or to relate to the cognitive aspects of emotion; thinking can alter our feelings of euphoria or anxiety. Here are some sources that may be useful when you are revising, primarily for altruism.
The first source is an RSA animate of a talk by Jeremy Rifkin. Jeremy Rifkin talks about how humans are biologically "soft wired" for empathy and that we can extend our empathy to others by extending our social identities to include the entire human race as well as other creatures. Rifkin claims that anti-social behavior, such as violence are secondary to our nature and are affected by sociocultural factors. His talk partly relates to biological factors for emotion - when other people are communicating their feelings, our mirror neurons create the same feelings in us. Therefore, when you are in need of help it is essential that you communicate your emotions to others as well as you can. The social identity theory (SIT) or kin selection theory may be arguments that can be used against his claim. As you all know, according to these theories, we have a tendency to "help and stick to our own kind" or our in-groups. One may ask if it our brains are capable of including all creatures on earth in our in-group in thought as well as in action. According to SIT our self identity is defined by this exclusion and inclusion of others. In his talk Jeremy Rifkin relates to research on mirror neurons. I think I showed you the first part of a documentary on mirror neurons a long time ago. Mirror neurons can be used as an example of how our biology influences our behavior as well as a biological factor influencing emotion. It is also a biological support of social learning theory. Speaking about social learning, I want to inform you that for dogs, barking and peeing with one leg lifted seems to be learned by imitation. As you might know, we taught our chihuahua Teddy not to bark and not to pee with his leg lifted (because I live in a condo and don´t want to disturb neighbors or have my walls spoiled) However, now when Teddy has seen other dogs lift their legs while peeing and heard them bark he is showing slight tendencies for these behaviors. Please do not use this last anecdote in any of your essays!!! If you are using Dan Batson´s empathy-altruism hypothesis as an empathy you may consider this article that is written by him: Empathic concern and empathy in humans It mentions a recent study by Batson where female participants read a story about Kayla who was being rehabilitated after a broken leg. Kayla was either a student, a child or a dog depending on the experimental condition. Interestingly enough, participants reported more empathic concern for the dog or the child than the student, implicating that empathic concern is more than just identification (because in that case participants who were students, should have identified more with Kayla the student) Another study than the Carol study that you all know of supporting Batson´s hypothesis is a study from 1983 where participants watched a confederate (unknowingly to participants) receiving electric shocks. They either watched him receive shocks over two trials or ten trials. After watching the trials participants had to answer questions about their emotional state. After filling out the questionnaire, participants were informed that the confederate had had a traumatic experience with electric shock during childhood and were therefore asked to take the remaining shocks in the confederate´s place. If participants had a high distress score as measured by the questionnaire they were more likely to accept the offer, supporting the view that we are more likely to help when we can empathize (which may be made possible by our mirror neurons). In regards to the "dog versus human" study I find it amusing that participants had more empathic concern for a dog than a full grown student, which may be because we a similar bonding with our pets as with our children. A study from 2003 has shown that when people pet their dogs, oxytocin is released in the dog as well as in the human. Oxytocin, which is another example of how hormones influence our behavior, is related to bonding, trust and helping behavior and is therefore a biological factor of altruism. More on oxytocin and bonding with pets can be read on this blog page (recommended to me by Chaya): Pampered pooch syndrome In regards to dispositional factors for altruism, Nicky sent me this link a long time ago: Oliner & Oliner This is the study of heroic rescuers that we have talked about in class. It may be used as an example of dispositional factors for behavior and maybe as part of an evaluation of bystander theories (even though there may be situational factors for bystanderism, some people may be less prone for bystanderism than others) The same may be used during evaluation of altruistic theories. There may of course also be social and cultural factors influencing both altruism and bystanderism. In an early presentation of altruism I mentioned the hypothesis of strong reciprocity, that states that we are more likely to help people in a group if a social norm of reciprocity and cooperation has been established. Conversely, if an egoistic norm has been established, we should be less likely to help others. We are also likely to punish those that break the social convention of helping. This behavior has been observed in humans as well as in animals. This possible "innate sense of fairness" has recently been observed in an interesting study on babies. Situational factors can also affect altruism. In one study, scientists compared survival rates of men, women and children between the sinking of Lusitania and the sinking of Titanic. The sinking went much faster for the Lusitania than the Titanic, and consequently more men and less women and children survived the Lusitania compared to the Titanic. The explanation is that because the sinking of the Titanic went so fast, men were more likely to follow their basic instinct rather than their internalized norm of allowing children and women to board the lifeboats before them. In a similar study, Dr Aguirre analyzed the records of a deadly nightclub fire and found that those who were alone in the nightclub were more likely to survive than those that were with friends or relatives (further support for SIT and kin altruism): How the men reacted as the Titanic and Lusitania Went Under Friends of mine, by the way, claim that feminism may eventually change the norm that women are to be saved before men if the lives of a group of people is at stake (as implied by the saying "women and children first"). But this is a new discussion in itself. In my previous post I mentioned Derren Brown. I therefore got the idea that maybe I should link to a few interesting videos with him. By the way, many people think that what is happening is fake and conducted by actors. I am not so sure, as hypnosis does work on some people and at times when we are suggestible. However, I am pretty sure that he was not always successful (they only show when he is successful). The experiments he is performing may sometimes be considered unethical and impossible to conduct by psychological researchers without a law suit. For television, however, almost everything seems to be acceptable...This is a clip with him on subliminal advertising (with an explanation):
This is a clip with him on the psychological phenomenon of person swap: Here is a clip where he hypnotizes a pedestrian that she is stuck to the ground I think I have shown you this clip in class - When he hypnotizes a man on the street to give him his house keys In the following clips he uses a computer game to hypnotize a man to believe he is in the computer game and have him shoot at Zombies for real. Although a bit scary (and unethical), it shows that what took place in the movie The Manchurian Candidate might actually be possible. Waking dead - part 1 Waking dead - part 2 In the following episode, he manipulates a man who has a phobia of flying to land a plane. It features the "smoke in the room" bystander study that Derren uses to pick the person who is most suitable for the show. Brown was influenced by the movies The Game, Fight club and Donny Darko when creating the show. Hero at 30.000 feet - part 1 In this episode, Derren Brown travels around the world to fool some experts on the supernatural that he has supernatural powers by using various tricks. In this episode, he tries to convert a group of atheists to religiosity. He is also holding a seance where he uses a trick called cold reading (it can be explained by a combination of confirmation bias, reading of facial expressions, and guesswork/general statements by the cold reader) Confirmation can also explain illusory correlations, as you already know. How successful he is can be seen here: Messiah Apparently, Derren Brown is most proud of the following episode: The heist - part 1 In this episode, Derren hypnotizes people into robbing an armed truck. While choosing the persons to hypnotize, Derren used the Milgram experiment. I have shown the Milgram part in class. Besides hypnosis he is also using NLP techniques. In this last clip I recommend by him (there are many, many more with Derren Brown) you can try how hypnotizable you are yourself. I however doubt that you will be hypnotized because you are too aware of the techniques he is using (and even less now because of what I just said) But may I tell you that this trick works better if you are seated in an armchair or a sofa: Derren Brown - stuck to chair If you are interested, Derren Brown also has his own web site It was when I was looking for some research to explain why relationships end or change that I came across Dr Rogge's research. Dr Rogge has conducted research that can predict breakups by exploring the participants' hidden/unconscious feelings to their partner:
Relationship test accurately predicts breakups Negative emotion, which is a factor that Gottman also emphasizes, therefore seem to be an important factor for the ending of relationships. However, even though negative emotion is a good predictor of breakups, these studies are only correlational. It may well be that there are other factors that have caused the negative emotions. As problems with communication is a major factor, Dr Rogge's recent research on 220 newly weds therefore shows some interesting results. According to the current data, finances is a more common problem than communication difficulties. As with most psychological phenomena, the reason why people break up is a complex matter. You may also want to look up the series The science of attraction if you want to learn more about the biological (e.g. smell), psychological (e.g. the halo effect) and social origins of attraction (e.g. familiarity). I have shown a few of the clips in class. The series are presented by Derren Brown. Derren Brown, by the way, is an illusionist who became famous for a TV series called mind control. He has made many entertaining programs where he has influenced people using psychological tricks, such as hypnosis and subliminal influence. Parts of these episodes can be found on Youtube. One social origin of attraction is, as you already know, familiarity. A long time ago Chaya recommended a blog article on this topic; Why familiarity breeds contempt. In the article, the author relates to research that familiarity only breeds liking to a certain extent. Studies show that familiarity only breeds initial liking, but if people are dissimilar to each other, being all too familiar with someone can actually breed disliking. Something you can consider when you evaluate research on the mere exposure effect. Similarity or perceived similarity is a psychological origin of attraction. Nicky sent me an interesting article on the topic some time ago; Why do couples start to look like each other? Studies have shown that couples in successful marriages are very similar to each other. However, these studies are only correlational, and it is therefore possible that being together can make you more similar to each other, for instance by acquiring similar habits. This "growing together" may be the reason why they say that dogs look like their owners. In one experiment, Zajonc demonstrated that partners tend to imitate each others facial expressions and thus may become more physically similar over time. If you want to see a documentary that relates to culture and relationships you can watch Louis Theroux's weird weekends - Thai brides This documentary was recommended to me by Ling and is about older western men that marry young Thai women through a dating agency. You may see some examples of cultural misunderstandings in the documentary, but foremost examples of stereotyping of Thai women. An interesting psychological phenomenon in regards to relationships is the "frenemy"; a friend or a partner that also is a competitor/rival and that you may have a dislike or even hate towards. The feeling is mutual, yet you stay friends/partners because of a mutual dependence on each other. How you can use this concept in any of your essays, I have no clue. The only situation I can think of is if you are talking about why relationships end. Dislike does not necessarily lead to the end of a relationship. One learning outcome of the biological level of analysis is to explain functions of at least two hormones in human behaviour. Two hormones that can be used besides adrenaline is testosterone and estrogen. Testosterone is related to libido, memory, depression, and aggression (you may therefore mention testosterone as a factor when you evaluate sociocultural explanations of violence). Estrogen is related to libido, depression, obsessive compulsive behavior, bulimia nervosa and memory.
There are age differences, socioeconomic differences and cultural and racial differences in regards to production of sex hormones. For instance, older people tend to have lower testosterone levels than younger men and people with a lower socioeconomic status tend to have higher testosterone levels than people with higher socioeconomic status. It is important to emphasize that the research has only found a correlation between certain behaviors and sex hormones. It is therefore likely that environmental (such as diet, stress), social (e.g physical labor) and cultural factors can alter hormonal production. Therefore, individuals with lower socioeconomic status may commit more felonies and be more likely to suffer from learning difficulties than individuals with higher socioeconomic status. Their higher testosterone production, however, may more be a symptom of their situation and not the cause of their behavior. |
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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