Brain & Behavior
What’ s the brain technique used in Antonova's study?
fMRI
Define pheromone
Pheromones are chemical messengers that produced and released into the environment by an animal affecting the behavior or physiology of others of its own species.
Twin study, adoption study and family stuides are the common research methods in all topic of psychology. True/False
False
True or False. The MRI is a static image that does not demonstrate activity.
True.
Does the method of molecular genetics base on the principle of genetic similarity? Yes/No
No
a decrease in the number of synapses as a result of the removal of dendritic branches. It is the process carried out in the brain to increase its efficiency.
Identify the concept
Neural pruning
Hormones influence human behavior directly. True or False.
False.
Hormones do not influence behavior directly. Instead, they change the probability that a certain behavior will occur in response to a certain environmental stimulus.
What's the two main aims for evolution?
The primary purpose for evolutionary adaptation is firstly to survive, with the ability to survive described in the phrase ‘survival of the fittest’. The second purpose for any behaviour is to increase the chance of reproduction.
True or False: The reasons for neuroplasticity are environmental (e.g., injury, or simply learning new skills).
False. The reasons for such changes are both genetic (normal pre-programmed development of the brain)and environmental (e.g., injury, or simply learningnew skills)
Describe the research method used in Kendler‘s study
Correlation
Describe the difference between excitatory neurotransmitters and inhibitory neurotransmitters.
Excitatory neurotransmitters increase the likelihood of a neuron firing by depolarizing the neuron. Excitatory neurotransmitters include acetylcholine.
Inhibitory neurotransmitters decrease the likelihood of a neuron firing by hyperpolarizing the neuron. Inhibitory neurotransmitters include GABA.
What's the independent variable(s) in Scheele's study?
1. Receive oxytocin or not
2. in a stable relationship or single
What's diathesis stress model?
It attempts to explain behavior as a predispositional genetic vulnerability expressed as a result of stress from life experiences.
Why is the understanding of neural plasticity important in our understanding of the localization of behavior in the brain?
By measuring the increase in grey matter in a specific part of the brain as the result of learning a new task, for example, we then can assume that this part of the brain was firing more frequently, leading to dendritic branching.
Define concordance rate.
The concordance rate is the percentage frequency of the same trait in the two people being researched.
Explain the relationship between neurotransmitter and Agonist.
All neurotransmitters are agonists for receptor sites. Drugs can also be agonists. Since they are external to our system, they are referred to as exogenous agonists.
Describe two differences between hormone and neurotransmitter.
1. A hormone is a chemical that is secreted by glands in the endocrine system. Unlike neurotransmitters, they are released directly into the blood stream.
2. Hormones take longer to produce changes in behavior than neurotransmitters. However, they also produce effects that last a lot longer than an action potential.
Explain one reason why the researchers do not conduct experiment in the field of gene and behavior.
1. it is unethical to manipulate human genes
or
2. it is difficult to control confounding variables such as the influence of specific environment.
Many studies that use MRI or fMRI scans have small sample sizes. Give one reason for this phenomenon.
This is because the use of scanning technology is very expensive.
List one specific factor preventing genetic expression.
Diet, exercise, stress and hormone.
How does the use of MRI help Draganski get causal conclusion？
The multiple use MRI allows the researcher did pre-post test on participants‘ brain structures, which shows the change of brain structure. MRI is ethical so it can be repeatedly used.
Try to find a possible explanation for the mixed results of zhou and Hare
They use different task on gender identification which may have different level of ecological validity.
List two limiations of evolutionary theory.
1 The influence of genetics on behavior is not clear
2 Cultural variation
3. Evolutionary explanations for behavior are difficult-–and in many cases impossible—to test.
4. Much of the research to test evolutionary theories is highly artificial and lacking ecological validity.
Predict the result of the study and explain your reasoning.
Thirty-three women participated in this study, including women with early childhood sexual abuse and PTSD (N=10), women with abuse without PTSD (N=12), and women without abuse or PTSD (N=11). The researchers used an MRI to measure the volume of the hippocampus in all of the participants - and a PET scan to measure its level of function during a verbal declarative memory test.
Women that were abused and showed symptoms of PTSD were found to have a 16% smaller volume of the hippocampus compared to women with abuse without PTSD. In addition, these women showed a lack of activity in the hippocampus when carrying out the memory task. Women with abuse and PTSD had a 19% smaller hippocampal volume relative to women without abuse or PTSD.
In conclusion, long-term stress appears to lead to hippocampal atrophy - that is, hippocampal cell death that leads to a smaller hippocampus.
Often the concordance rate in twin studies is less than 100%, even in MZ twins. Why might this be true? (Please give at least two reasons.)
There are several reasons why the concordance rate may not be 100%. One reason has to do with gene expression. It may be that both twins have the genes for a behavior, but that not all of the genes are expressed so that behavior is not observed. This does not mean, however, that there is not a genetic root to the behavior.
It could also have to do with the way the behavior is measured. Often behavior is self-reported - for example, one's sexuality. Or it is based on a diagnosis. In that case, it may be that the diagnosis was not valid, or that some of the controls actually may have the disorder, but have not gone for diagnosis.
Finally, it could be that there are purely environmental factors that play a role in the behavior; however, until we are able to better map the functions of the 22.000 human genes, we cannot 100% support this response, since a lack of gene expression cannot be ruled out.