Outline the principles that define the biological level of analysis.

Explain how principles that define the biological level of analysis can be demonstrated by research or theories.

1. Emotions and behavior are products of anatomy and physiology of the nervous and endocrine systems.

a. For example: The amygdala is part of the limbic system and is involved in the regulations of the emotions of fear and rage.

2. Patterns of behavior can be inherited.a. Evolutionary psychology and the study of genetics – if a behavior exists today it must

have helped a species survive and reproduce in the past, introduced by Darwinb. Humans have changed physically and behaviorally to adapt to the environment – with a

disorder there is usually a predisposition while environmental factors play a role as wellc. For example: Holland Twin Study

i. Aims : To investigate whether there was a higher concordance rate of anorexia nervosa for Mz than Dz twins.

ii. Procedure : 34 pairs of twins (30 female and 4 male). 1 set of triplets. Physical resemblance questionnaire established whether the twins were Mz (16 pairs) or Dz (14 pairs). If there was any uncertainty a blood test was carried out. Longitudinal study - over time. Clinical interview and standard criteria used to diagnose anorexia.

iii. Findings : Significant difference - much higher concordance rate for Mz (56%) than Dz (7%) twins. Further findings - in 3 cases where the non-diagnoses twin did not have anorexia, they were diagnosed with other mental illnesses, and 2 had minor eating disorders.

iv. Conclusion : Genetic basis for Anorexia suggested. Genes not wholly responsible constitute a pre-disposition. Individual vulnerable but the disorder is not triggered. Implications include the need to identify precipitating factors ie, environmental triggers.

d. Problem with evolutionary psychology is that they can only study relationships and it is difficult to prove any given theory.

3. Animal research has enhanced our understanding of behaviora. For example, Pavlov’s experiment on dogs

i. Classical conditioning: type of learning in which an organism comes to associate stimuli

ii. Classically conditioned dogs to salivate to the sound of a bell.iii. When a dog sees food (unconditioned stimulus) it salivates which is the

unconditioned responseiv. When it hears a bell, it does not salivatev. But when hearing a bell and given food (unconditioned stimulus) it salivates

vi. Then by just hearing the bell (conditioned stimulus) it will begin to salivate (conditioned response)

b. Problem with animal research is the ecological validity is low because people have different brains and will react differently than animals.

c. Some people also think experimenting on animals is unethical.

Using one or more examples, explain the effects of neurotransmission on human behavior.

1. Neurotransmitter: Neurochemical that transmits nerve muscles across a synapse and causes excitation or inhibition of another neuron. Depending on the kind, each has a different impact on human behavior.

2. Acetylcholinea. Deterioration of Acetylcholine leads to Alzheimer’s b. Study to cite: Martinez and Kesner

i. Aim: To determine the role of acetylcholine on memoryii. Methodology: Performed an experiment on rats, they were trained to run a maze

with food at the end. After trained, one group was injected with scopolamine which blocks acetylcholine receptor sites. A second group was injected with physostigmine which blocks the production of cholinesterase thus acetylcholine was more readily available. The third group was injected with nothing.

iii. Findings:-Group 1: Slower at finding way through maze.-Group 2: Faster.-Group 3: Control

iv. Limitations: Ecological validity: rats are not humans.v. Conclusion: Acetylcholine plays a major role in memory.

c. It is found in the spinal chord, brain, and peripheral nervous system; aids in learning and memory; helps us to breath, pay attention, stay motivated, and enables muscle contraction

d. Without acetylcholine our memory skills are impaired, thus linking this to Alzheimer’s. Alzheimer’s patients show significant brain shrinkage and there is a link to diminished acetylcholine.

3. Serotonina. Serotonin is the neurotransmitter that effects sleep, arousal levels, and emotion.

Research suggests that depression may be caused by malfunctioning neurotransmitter systems.

b. One of the theories that supports this is the Catecholamine Hypothesis – depression is associated with lower levels of nor adrenaline and serotonin is the transmitter responsible (became known as the serotonin hypothesis).

c. Study to cite: Janowsky ey al (1972)i. Participants became very depressed when given the drug physostigmine

ii. Demonstrated that some cases of depression may be linked to a disturbance in neurotransmission.

d. Limitation of studying serotonin: There is no way to study the amount of serotonin in humans so this theory is really difficult to test. No way to verify evidence.

e. Postmortem studies of brains of depressed people show lower levels of serotonin.f. Depression cannot be explained simply on a biological level, there are cognitive and

sociocultural aspects. g. Serotonin levels also play a role in arousal. Study to cite: Kasamatsu and Hirai (1991):

i. Aim: To see how sensory deprivation affects the brain.ii. Methodology: Studied a group of monks, took blood samples before ascending

the mountain and immediately following the reports of hallucinations.iii. Findings: After 72 hours on a cold mountain with nothing to eat and unable to

speak, the monks began to hallucinate and higher levels of serotonin were observed.

iv. Conclusion: Sensory deprivation had led to higher levels of serotonin which activated the hypothalamus and frontal cortex resulting in hallucinations.

Discuss how and why particular research methods are used at the biological level of analysis.

1. Experiments on humans and animalsa. Study to cite: Rosenzweig and Bennet (1972)

i. Aim: Investigate brain plasticity – the brain’s ability to rearrange connections between its neurons as a result of an enriched or deprived environment

ii. Methodology: Separated the rats into two groups and placed one group in an enriched environment characterized by interesting toys to play with. The other group was placed in a deprived environment with no toys. The rats spent 30-60 days in their environment and then were sacrificed.

iii. Findings: Postmortem studies of their brains showed that the rats in the stimulating environment had increased thickness in the cortex (frontal lobe associated with thinking, planning, and decision making).

iv. Limitation: Some experiments cannot be done on humans so there is low ecological validity.

2. Postmortem Studiesa. Study to cite: Broca (1861):

i. Studied the brain of Tan, a patient whose brain damage occurred in the left frontal lobe of the brain

ii. Findings: The left frontal lobe is critical for the production of speech iii. The effects of damage to Broca’s area (loss for producing coherent speech) are

mostly observed in stroke victims, many who are temporarily or permanently unable to produce speech, known as Broca’s aphasia.

b. Limitation: Damaged brains are not the same as healthy ones3. Correlational Studies – comparisons of data, give us a lot of information on inheritability

a. Study to cite: Holland twin studyi. Aims: To investigate whether there was a higher concordance rate of anorexia

nervosa for Mz than Dz twins.ii. Procedure: 34 pairs of twins (30 female and 4 male). 1 set of triplets. Physical

resemblance questionnaire established whether the twins were Mz (16 pairs) or Dz (14 pairs). If there was any uncertainty a blood test was carried out. Longitudinal study - over time. Clinical interview and standard criteria used to diagnose anorexia.

iii. Findings: Significant difference - much higher concordance rate for Mz (56%) than Dz (7%) twins. Further findings - in 3 cases where the non-diagnoses twin did not have anorexia, they were diagnosed with other mental illnesses, and 2 had minor eating disorders.

iv. Conclusion: Genetic basis for Anorexia suggested. Genes not wholly responsible constitute a pre-disposition. Individual vulnerable but the disorder is not triggered. Implications include the need to identify precipitating factors ie, environmental triggers.

b. Limitations: cannot infer causation, there’s bias in questionnaires, interviews, etc.

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

1. fMRI: Formed using magnetic fields / radio waves to create computer generated imagea. advantages: look at working brain (used to compare teen/adult brains). No radioactive

injections, most hospitals have these, can see localized brain function through blood flow

b. disadvantage: not all tasks require blood flow= infallible/ require training to read, interpret, design a study

2. PET: brain is injected w/ radio active form of glucose à as brain performs certain tasks areas in use become visible “hot spots”

a. advantages: allows theories for what areas are active (participate) during certain brain functions

b. disadvantage: Does not give cause for brain function, technique is expensive/ hard to interpret

3. CAT- takes slices of x-rays of the brain and uses injected contrast materials to check for blockages/ blood vessel problems within the brain.

a. Advantages: Helpful in determining where in the brain problem area is that may be causing disease/ mental disability.

b. Disadvantage: does not show causation of clot/ problem4. EEG - shows electrical activity through electrodes

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

1. Consent – patients with brain damages or disorders may not always know what they are consenting to.

2. Protection from harm/discomfort – many tests can only be done on animals and some say this is unethical, also this makes the ecological validity of the research questionable because animals are not the same as humans.

3. Confidentiality – Undue stress, particularly in relation to genetic research (stem cell research) – many people find this unethical.

4. Explanation of what the researchers are studying up front, should provide a detailed explanation at the end.

Explain one study related to the localization of function in the brain.

1. Broca: a. Discovered an area in the left frontal lobe that is critical for the production of speech

(discovered this by conducting a post mortem autopsy on ‘Tan” and many other patients)b. The effects of damage to Broca’s area (loss of producing coherent speech) are mostly

observed in stroke victims, many who are temporarily or permanently unable to produce speech, this condition is known as Broca’s aphasia

2. Wernicke:a. Demonstrated that damage to another area in the left temporal lobe disrupts the ability

to comprehend or produce spoken or written languageb. The condition known as Wernicke’s aphasia has symptoms such as problems

understanding speech of others or may substitute wrong words into planned phrasesc. His research was found based on post mortem autopsies as well

3. Specific parts of the brain are responsible for specific brain activities. Gave us insight to where language is stored in the brain.

4. Limitation: Postmortem research on a damaged brain, may not relate to a healthy brain

Using one or more examples, explain the function of two hormones on human behavior.

1. Testosterone:a. Signal sent from pituitary gland to testes (in men) or ovaries/adrenal glands (in women)

for testosterone production. b. Testosterone increases libido (sex drive), there’s a connection to aggression/risk takingc. Study to cite: Penn State University Study:

i. Showed military men with higher testosterone levels were more likely to smoke, have STDs and take risks.

d. Too much in women: muscular body, high libido, development of male characteristics.e. Too little: decreased libido, irritability, depression, fatigue.

2. Oxytocina. Secreted by the posterior pituitary glandb. Plays role in female reproduction, social recognition, and maternal behaviorsc. “cuddle chemical” – helps induce more, plays role in breast feedingd. Study to cite: Morhenn et al (2008):

i. Methodology: Randomly assigned students to a massage-and-trust, rest-and-trust, and massage only groups. The massage was 15 minutes long. Participants then played a trust game in which you had to lend another participant money. Sending a large amount of money indicated a high level of trust. Blood was taken before the experiment and close to their decision in the trust game to measure oxytocin levels.

ii. Findings: Participants who received massages and participated in the trust game sent back a lot of money suggesting that oxytocin’s effect on behavior is to increase generosity and cooperation among adults.

e. Too little: reduced sensitivity (maternal abuse), possible connection to autismf. Too much: reduces exertion of urine, distress in infants, reduced sodium exertion

Discuss two effects of the environment on physiological processes.

1. Melatonin – Jet Lag.a. Secreted by pineal gland at the base of the brain during darkness; seems to sense

changes in light and relies on senses for information about time of day, temperature, etc. Sends info to pituitary gland which then, turns off other hormones that stimulate the body. Helps us sleep.

b. Jet lag occurs when a person traveling by plane, usually west to east across time zones, late experiences tiredness during the day, being unable to sleep at night, having low levels of concentration, and disturbances in digestion and appetite.

c. It results from incompatibility between the information about the time we receive from the environment (through exposure to light) and the information we have in our brain about what stage in our sleep-wake cycle we should be in. Melatonin is not released in our brains at the right times – causes drowsiness during the day and inability to sleep at night.

d. Melatonin can therefore be taken in pill form to help reprogram the brain to fit with our new location.

e. We can train ourselves to adapt to the location by sleeping only at specific times for a limited amount of time while flying so were prepared for the destination when we get

there. 2. Neuroplasticity – concept that although there seems to be localization of brain function, the

specific location is not necessarily fixed in all people and if necessary, the brain seems to be able to adapt to environmental demands.

a. Study to cite: Rosenzweig and Bennet (1972)ii. Aim: Investigate brain plasticity – the brain’s ability to rearrange connections

between its neurons as a result of an enriched or deprived environmentiii. Methodology: Separated the rats into two groups and placed one group in an

enriched environment characterized by interesting toys to play with. The other group was placed in a deprived environment with no toys. The rats spent 30-60 days in their environment and then were sacrificed.

iv. Findings: Postmortem studies of their brains showed that the rats in the stimulating environment had increased thickness in the cortex (frontal lobe associated with thinking, planning, and decision making).

v. Limitation: Some experiments cannot be done on humans so there is low ecological validity.

Examine one interaction between cognition and physiology in terms of behavior. Evaluate two relevant studies.

1. One huge interaction between cognition and physiology is memory. 2. Study to cite: Amnesia and HM Study:

a. HM had brain surgery to remove the medial temporal lobes in order to correct his epilepsy.

b. HM’s surgery did not go as planned and the hippocampus was also removed, and this had profound effects on his memory. He could not create long term memories – had retrograde amnesia – loss of memory before an event (the surgery).i. Limitation: Cause and effect was hard to establish and HM was using anti-epileptic

drugs which could have caused further damage to his brain.c. Memory is a biological process.

3. Second study to cite: Acetylcholine a. Martinez and Kesner on the role of neurotransmission in learning and memory:

i. Aim: To determine the role of acetylcholine on memoryii. Methodology: Performed an experiment on rats, they were trained to run a

maze with food at the end. After trained, one group was injected with scopolamine which blocks acetylcholine receptor sites. A second group was injected with physostigmine which blocks the production of cholinesterase thus acetylcholine was more readily available. The third group was injected with nothing.

iii. Findings:-Group 1: Slower at finding way through maze.-Group 2: Faster.-Group 3: Control

iv. Limitations: Ecological validity: rats are not humans.v. Conclusion: Acetylcholine plays a major role in memory.

b. It is found in the spinal chord, brain, and peripheral nervous system; aids in learning and memory; helps us to breath, pay attention, stay motivated, and enables muscle contraction

c. Without acetylcholine our memory skills are impaired, thus linking this to Alzheimer’s. Alzheimer’s patients show significant brain shrinkage and there is a link to diminished acetylcholine.

With reference to relevant research studies, to what extent does genetic inheritance influence behavior.

1. Anorexia – Holland and the twin studya. Aims: To investigate whether there was a higher concordance rate of anorexia nervosa

for Mz than Dz twins.b. Procedure: 34 pairs of twins (30 female and 4 male). 1 set of triplets. Physical

resemblance questionnaire established whether the twins were Mz (16 pairs) or Dz (14 pairs). If there was any uncertainty a blood test was carried out. Longitudinal study - over time. Clinical interview and standard criteria used to diagnose anorexia.

c. Findings: Significant difference - much higher concordance rate for Mz (56%) than Dz (7%) twins. Further findings - in 3 cases where the non-diagnoses twin did not have anorexia, they were diagnosed with other mental illnesses, and 2 had minor eating disorders.

d. Conclusion: Genetic basis for Anorexia suggested. Genes not wholly responsible constitute a pre-disposition. Individual vulnerable but the disorder is not triggered. Implications include the need to identify precipitating factors ie, environmental triggers.

2. Depression – Nurnberger and Gershon (1982)a. Reviewed the results of seven twin studies and found that the concordance rate for

major depressive disorder was consistently higher for Mz twins than for DZ twins. b. Average concordance rate for MZ twins: 65%c. Average concordance rates for DZ twins: 14%d. Supports the hypothesis that genetic factors may predispose people to depression.

Examine one evolutionary explanation of behavior.

1. I don’t really know

Discuss ethical considerations in research into genetic influences on behavior.

1. Labeling – Labeling Theory and stigmatisms a. Labeling has a significant negative effect on a person’s subsequent treatment by other

peopleb. Can lead to stigmatisms - Read (2007) showed attitudes towards those diagnosed in a

medical context tend to be characterized by fears; knowing someone has a mental diagnosis increases reluctance to date them

2. Confidentiality – privacy is not always guaranteed, if we really wanted to we could probably find out who HM is

3. Moral considerations – is stem cell research right or morally okay?4. At what percentage of risk of having a disorder do you really worry? Are there other

environmental factors?