2.1-2.3 BLA Outcomes

Biological Level of Analysis

2.1 Physiology and Behavior

First of all, the biological level of analysis argues that there are physiological factors that affect behavior in organisms. It should be noted, however, that physiology is not the only factor that impacts behavior. The environment and cognition may interact with biological systems and affect physiology. Biology can affect cognition, and cognition can equally affect biology. (The two are bidirectional). The biological level of analysis takes on a reductionist view - they believe that behavior is caused by biological factors (e.g. hormones, neurotransmitters, etc.) This reductionist view is often criticized for being overly-simplistic for explaining behavior.

<NATURE V.S. NURTURE EVENT>… "Is behavior a result of biological factors or environment?"

(IB psychology takes on an interactionist approach: meaning they do not rely solely on either biological or environmental factors)

- Outline principles that define the biological level of analysis

1) Behavior can be innate because it is genetically based (What you do naturally, on instinct. This is a result of evolution)

2) Animal research can provide insight into human behavior. This is why a lot of research is done on animals.

3) There are biological correlates to behavior - hormones, proteins, metabolism and neurotransmitters are all known to affect the behavior of a person.

               

- Explain how principles that define the biological level of analysis may be demonstrated in research (through theories or studies)

1) There are biological correlates of behavior: Newcomer at al (1999) performed an experiment on the role of the stress hormone cortisol on verbal declarative memory. Cortisol is a hormone that is known to interfere with your memory. He collected a total of 51 people for an experiment that tested memory and cognitive functions before and after treatment of high doses or low doses of cortisol, or inactive substances (=control substance). As a result of this experiment, Newcomer et al observed that memory impairment happened only in the individuals who were treated with high doses of cortisol, after only four days of exposure. However, the researchers also found out that this memory loss was only temporary as after a week of having a wash-out period, all the subjects’ memory performances returned to their untreated levels. This experiment shows that there are biological correlates to behavior – in this case, cortisol being a hormone that affects the memory performance of an individual.

More on this experiment at: http://www.sciencedaily.com/releases/1999/06/990617072302.htm

(2) Animal research can provide insight into human behavior: This means that researchers use animals to study human physiological processes, because it is assumed that biological processes in animals are the same, or similar as in humans. One important reason for using animals is that there is a lot of research where humans cannot be used for ethical reasons (such as hurting the subject). The use of animal research in order to provide insight into human behavior can be demonstrated in the studies of Martinez and Kezner (1991), where an experiment was carried out studying the role of neurotransmitters in learning and memory. (This is an experiment that used various chemicals to test acetylcholine, which is responsible for memory retention.) The mice’s brains were altered and observed – the results were generalized to humans as well.

(3) Human behavior innate, and thus genetically based: Researchers interested in the genetic origin of behavior often use twin studies so they can compare one twin with the other on a variable such as intelligence, depression or anorexia nervosa. Bouchard et al (1990) who performed the Minnesota twin study, a longitudinal study investigating the relative role of genes in IQ. He found that IQ was affected by environment, but also have genetic influences as well. This shows that some behavior (such as a person’s intelligence) is innate (such as in one’s genetic material).

               

- Discuss how any why particular research methods are used at the biological level of analysis

- Discuss ethical considerations related to research studies at the biological level of analysis

Laboratory experiments: At the biological level of analysis, lab experiments are commonly used to establish cause and affect relationships between the variables that are being studied. A key point at this level of analysis is the use of animal experiments as well as human experiments. When researchers want to test the degree of changes to physiology (i.e. by injection of neurochemicals or hormones) or to test the effectiveness of a new medication, lab experiments are used. Ethical considerations should always be made; when the researchers are testing new medications, the results are unpredictable - the patient's health and well-being cannot be guaranteed. The patients should be fully aware of the study they are taking part in. Their personal identities should also be protected. Using ‘codes’ or listing the patients as ‘anonymous’ will help protect the patient’s identities. Laboratory experiments are useful because they allow the researchers to make accurate conclusions and establish clear cause and effect relationships.

Case Studies: The case study is another way to carry out research on human participants, as well as on animals. Instead of causing some kind of change to a person’s physiology, researchers can take advantage of naturally occurring irregularities (e.g. SEVERE brain damage or long term drug use) by obtaining detailed information about the participant’s condition. As this approach is mostly descriptive, there is relatively little harm that can be done to participants. This means that there are less ethical concerns that in lab experiments – the irregularities are present before the researcher studies the subjects. The most important ethical concerns for case studies are the depth of information that the researcher has access to and the researchers' steps to protect subject anonymity. The depth of information affects the subjects because the information has the potential to affect their daily lives. For example, if they are notified by the researcher that they have a mental disability, this could harm the subject’s self-esteem or confidence. Presenting or revealing the true names of the participants could harm their chances of living normal lives – getting jobs, for example. Thus, using pseudonyms or ‘anonymity’ is an acceptable way to protect the subject’s privacy.

- Explain one study of localization of function of the brain

Paul Broca (1861) was a psychologist who carried out a longitudinal study of a specific case where a patient was unable to speak, but could understand conversations. This patient was named Tan for he was unable to say anything except for the word 'tan'. Although he was mute, he was able to understand simple conversations. After Tan's death, Broca performed an autopsy and found that the left frontal lobe of Tan's brain was severely damaged. Broca came to the conclusion that the brain was localized - specific parts of the brain performed particular tasks that it was specialised to perform. Broca hypothesized that the left frontal lobe of the brain was responsible for tasks such as producing speech (locution) as well as deducing meaning from complex language, emotions, and analysis of syntax. Broca was one of the first psychologists to suggest that the brain was localized.

- Explain, using examples, functions of two hormones in human behavior

Hormones are a class of chemicals that affect behavior. They are produced by the glands that make up a system separate from the nervous system called the endocrine system. Unlike neurotransmitters, they are released into the bloodstream so they take a longer amount of time to produce changes in behavior, but are longer-lasting than neurotransmitters.

                1- Oxytocin is a hormone that is created by the hypothalamus after being stimulated by the pituitary gland. It is a hormone that is released by touches and hugs, and is associated with bonding between a mother and her child as well as between lovers. As a hormone, oxytocin plays a role by inducing labor contractions and lactation. Oxytocin is thought to change the brain signals that are related to social recognition via facial expression in the part of the brain that is responsible for processing emotional stimuli (that is, the amygdala). When oxytocin is injected into a healthy adult brain, the fear regulatory circuits are affected and there is an increase in trust and generosity of that person, so oxytocin is often called the love cocktail. Those who suffer from social anxiety (that is, the inability to trust) might therefore benefit from injection of oxytocin.

                2- Melatonin is another hormone that researchers think may help those with insomnia or jet lag. The production of melatonin is stimulated by darkness and is inhibited by light. Therefore, melatonin levels are high during the night (peaks in the middle of night) and low during the day (gradually decreases during the morning). Therefore, as winter approaches and the days become shorter, this means that we are inclined to feel more tired earlier.

Melatonin is a hormone that corresponds with the circadian rhythm (the internal 24 hour clock that we have in our bodies) and it is suggested that taking melatonin early in the evening helps one's ability to fall asleep. [However, if levels of melatonin are TOO high, this could lead to lethargy and sleepiness: for example, the short days of autumn and winter are known to affect the circadian rhythm of some people and cause a form a depression. This depression is called SAD - seasonal affective disorder. SAD is seen often in European countries with short hours of light during the day in winter, such as in Scandinavia. ]

- Explain, using examples the effects of neurotransmission on human behavior

Nerve cells, also called neurons, are the building blocks of behavior. These neurons send electrochemical messages to the brain so people can respond to stimuli that is either external (environmental) or internal (from internal changes of the body). The messages that are sent are sent by a method called neurotransmission. When an electrical impulse travels from the body of a nerve cell, it releases neurotransmitters which then cross synapses between nerve cells. Neurotransmitters are natural chemical messengers that transmit information from one nerve cell to another nerve cell. (The neurotransmitters are stored in the nerve cell's terminal buttons). After it crosses the nerve synapse, the neurotransmitters fit into receptor sites on the post-synaptic membrane and the message of the neurotransmitter is passed on. They can affect the mood, memory, sexual arousal or mental illness of a person. Acetylcholine is a neurotransmitter that is responsible for the development of memory, and serotonin is a neurotransmitter that can make a person sleepy or emotional.

- Discuss two effects of the environment on physiological processes

Page 46, brain plasticity: Before the 1960s, it was believed that the makings and the functionality of the brain was completely based on biological principles. However, Hubel and Wiesel (1965) found that the brain is equally stimulated and affected by the environment of which it is in. Hubel and Wiesel found that environmental enrichment can modify the brain (cerebral cortex, specifically). The brain is constantly changing as a result of experience and environment throughout the lifespan.

For example, brain plasticity is the brain's ability to change in order to enhance or increase learning or experience. The neural connections are remade and the structure of the brain is changed. It changes due to the challenges of the environment – the brain adapts. Appropriate learning and experience at certain times can increase the density of neural connections, which in turn allow the brain to be capable to learn EVEN MORE. This rebranching of neurons is called dendritic branching.

Rozenwig and Bennett (1972): researchers placed two rats in different environments to study the effect of either enrichment or deprivation on the development of neurons in the cerebral cortex. The rat with a lot of toys to play with (thus, the “enrichment” group) was found to have denser neural connections in the cerebral cortex. The rat with no toys had no particular thickness of neurons in the cerebral cortex. Also, the frontal lobes (which have to do with thinking) were heavier in the rats in the stimulating (enriching) environment. Therefore, we can infer that environment is a large factor that affects physiology.

*In other studies it was found that the thickest cortexes are found within rats that were placed in stimulating environments along with OTHER rats to interact with.

- Examine one interaction between cognition and physiology in terms of behavior

Humans themselves are able to change the functionality of the brain, as it was found in a study by Richard Davidson (2004). Eight Buddhist monks who have been meditating for a long period of their lives, and average adults who have trained in meditation for 100 hours were told to meditate on love and compassion. Using a PET scan, Davidson found that the levels of gamma waves produced were increased in all subjects during meditation. After meditating, he found that the monks' gamma wave production did not end, while the average subjects stopped producing gamma waves. (They had meditated on compassion for more than 10,000 hours in order to gain the rank of adept). Also, the gamma-wave area was seen to be larger in the monks than in the volunteers. Davidson argues that meditation can have significant long term effects on the brain and how it processes emotions. Therefore the brain can adapt to stimulation, either from external sources (such as the environment) or internal sources (such as cognition).

- Discuss the use of brain imaging technologies in investigating the relationship between biological factors and behavior

Modern technology is used often in neuropsychology because it allows researchers to understand and study the active brain. This in turn allows researchers to study the localization functions of the brain. Researches before modern technology often included invasive studies on animals, because animal researches allowed the brain to be understood. However, these invasive techniques involved scarring and ablation of brain tissue and parts of the brain, so there were extreme ethical concerns with them. The behavior of animals before and after the lesioning was compared and studied. In case of lesioning and scarring, the potential harm to animals cannot be determined, and damage that is caused to the animals cannot be reversed. This is a big ethical concern for animal research. The animals may feel pain as well. This is why modern imaging technologies such as EEG, PET and fMRI scans are popular and ethical ways of studying the brain and behavior.

The EEG is used by modern researchers to study the brain. The EEG is a printout that shows 'brainwaves'. The electrical charges of neural activity are shown in these printouts. However, the EEG is not helpful for the fact that it does not show what is happening in deeper brain regions, or the active functions of the brain.

PET scans monitor glucose metabolism in the brain. A patient who is getting a PET scan is injected a harmless dose of radioactive glucose, and its radioactive particles are detected by the PET scan as it transfuses throughout the brain. This scan has been used to detect tumors, changes in Alzheimer's and comparison of healthy brains and brains with mental disorders. Gur et al found (1995) found more active metabolism in the brain centers that control violence in men, than in women. The largest advantage to a PET is that it can record current activity, such as thinking.

fMRI scans provide 3D photos of brain structures by using magnetic fields and radio waves. It shows actual brain activity and can show active parts of the brain when it is engaged in behavior. They have high resolutions and thus are easy to study and carry out.

2.2 Genetics and Behavior

- Outline principles that define the biological level of analysis:

The biological principles that define the biological level of analysis are: 1) that all behavior is correlated to biological factors 2) animal researches can help researchers understand human behavior 3) human behavior can be innate because it is genetically based. The reason that we know that behavior has biological correlates is because we have found that certain hormones and neurotransmitters can affect one's mood or behavior. We know that animal researches are helpful to us to understand our own physiology because brain structures are very similar across different species. Finally, we know that behavior can be innate because evolution has caused us to have intuitive knowledge and certain instincts, such as being hungry.

- Explain how principles that define the biological level of analysis may be demonstrated in research:

In the study of intelligence and inheritance of intelligence, Scarr and Weinberg (1977) as well as Horn et al (1979) studied parents who raised both adopted and natural children. It was assumed that all the children involved in the study were brought up in the same environment, with the same upbringing with the same parents. Therefore, it was also hypothesized that any difference between the parent-child IQ correlations for adopted and natural children should be attributable to genetics (ie genetic makeup or DNA). However, the researchers found no significant correlations between the IQ of the biological parents and the adopted children. This indicates that intelligence could largely be affected by environment, rather than by nature because the adopted children came from poor backgrounds with parents who had considerably low IQ scores, while their adoptive parents were wealthy, white and middle class parents with high IQ levels. Therefore, this study actually contradicts the biological principle that 'there is always a biological correlate to behavior' because this study supports the theory that intelligence is affected by environmental factors rather than biological factors.

- Discuss ethical considerations related to research studies at the biological level of analysis:

At the biological level of analysis, particularly when studying genetics and behavior, adoption studies are performed often to study and directly compare genetic and environmental influences of behavior. Adoptive studies are studies where researchers try to determine if genetics influence an adopted child's behavior (in relation to their biological parents) or environment influences a child's behavior (thus the adoptive or foster family). Other research methods on the biological genetic level are twin studies and family studies. Twin and family studies generally study how genetics (such as DNA) can influence behavior. Some ethical considerations to make related to these types of genetic-biological researches is to make sure none of the subjects are directly influenced by the study's results. If a child who is adopted, but does not know so is involved in the study for adoptive studies, then the research should be covert. If this child were to find out that he/she was adopted without any prior explanation, then it would naturally come as a shock to the child. The emotional or internal burden that is a result of this would be a severe ethical concern.

- Discuss the extent to which genetics influence behavior

Genetic research in humans is largely based on study types called correlational studies. This is when researchers look at how different variables can co-vary. Therefore, correlational studies establish new relationships between variables, without the researcher manipulating any independent variables as they would do in an experiment. This is why, unlike experiments, no cause and effect of variables and factors can be determined in genetic research. Through these studies, such as twin studies, family studies and adoption studies, researchers are able to study the influences of genetics and the environment and determine the extent to which genetics influences one's behavior. Researchers have concluded that genetics does not completely dominate behavior, but many behaviors are influenced in various ways by genetic-makeup.

- Examine one evolutionary explanation of behavior

Evolution affecting behavior is one principle that is considered in the biological level of analysis. Darwin's theory of natural selection is one evolutionary explanation of behavior. Darwin states that members of a species (organisms) who have characteristics which better suit the environment in which they live will be more likely to breed and pass on their traits. This leads to evolutionary psychology, a field of psychology that suggests that as genes are mutated, the advantageous genes are passed on through the process of natural selection. Dan Fessler of the University of California at Los Angeles (UCLA) carried out research on the 'disgust' impulse in pregnant women. He found that the emotion of disgust has allowed our ancestors to survive long enough to produce offspring, who then passed on the same tendencies (the impulse of disgust) to us. According to Fessler, many of the diseases that are most dangerous to humans are food-borne, and this is why evolution and adaption has caused people (pregnant women especially) to have a disgust-impulse towards food - to diminish the risk of illnesses and infections. Overall, Fessler suggests that the view of disgust is a protection against disease.

- Discuss ethical considerations in research into genetic influences on behavior

Researches of human genetics focus and identify particular genes that are involved in hereditary diseases. These types of researches pose risks to participants because there is a link between genetic heritage and people's lives. Sometimes the genetic information is problematic for participants or their families (such as discovering a mental illness) and it can be stigmatizing and affect people's abilities to get jobs and insurance. In any study, participants should always understand their privacy and confidentiality will be protected, and any genetic information that is derived will be obtained as a part of the study. The aims and methods of the studies should be explained in full detail to participants, and they should sign a consent paper showing that they understand. Fully anonymizing the samples of the genetic information would protect the identity of the participants. 

2.3 Integrative Look at Criminal Behavior

 Today, many psychologists recognize that criminal behavior is very complex. It results from a combination of risk factors (which involve both biological and environmental factors) which interact and aggravate one another. The more risk factors that are present, the more likely one is going to engage in criminal behavior. There are several theories that suggest a specific root of criminal behavior. These roots are genetics, brain abnormalities and neurochemical imbalances.

Hutchings and Mednick (1975) studied adoption cases and found that if both the biological and the adoptive fathers had criminal records, then 36% of the sons also had a criminal record. If the biological father was the only one who had a criminal record, it dropped to 21% and if only the adoptive father had a criminal record, the rate of the child also having a criminal record dropped to 11%. When neither fathers had criminal records, the rate of sons having criminal records was 10%. This shows the importance of environmental factors, combined with genetic factors that determine whether or not one will hold a criminal record. A limitation to this experiment is the fact that children are often placed with adoptive families who are similar to their biological families. Some children were also placed into adoptive homes long after their birth, which means the early-experiences the child had with the biological parents could largely affect his/her behavior. It should be noted here that "criminal behavior" refers to even the smallest of crimes to the largest of crimes - from tax evasion to first degree murder. This word is used in such a general sense that results of studies that use the word "criminal behavior" could be inaccurate.

The brain is involved in emotion making of a person, and thus can be attributed to one's behavior. Emotions are controlled by the limbic system in the brain, and decision making takes place in the frontal lobe. Therefore, if there is an impairment of the pathways between the amygdala (which is responsible for emotional responses) and the frontal lobe,  the individual with the impairment might have difficulty in moderating emotional reactions. This will make social relationships difficult because the individual is not able to develop empathy or feelings of guilt, and thus acts more capriciously, without regard for the consequences.

Gender is also an interesting aspect to crime. 90% of apprehended murderers were male, as well as 82% who were arrested for violent crime. This is because of the low levels of serotonin in men links to antisocial and impulsive behavior. The most important thing to remember about biological factors and crime is that these factors are not the only cause for criminal behavior. It is only when these factors are combined with social and cognitive risk factors that violence and criminal behavior will occur.