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Prelim 2 DEA 1500 ANSWER KEY

QUESTION 1 Grader: Wangda

1. a. 3

Increases in lead are related to drops in IQ.

Changes in lead at lower levels affect changes in IQ more than at higher levels (nonlinear function)

There is considerable variability (heterogeneity) in IQ in relation to lead.

No one has 0 exposure to lead (everyone appears to have some lead present)

b. 2

Given the exponential drop off in IQ at low levels, there appears to be no safe levels of exposure to lead.

Even small increases in lead exposure at very low levels remain associated (are correlated) with IQ deficits

c. 4 2 for argument; 2 for counter

Exxon If the regulator standard for lead was raised, the impact on IQ is very small. For example, a shift in the current US standard of 10 µg/dl of blood to 20 µg/dl, on average only decreases IQ about 3 points.

You may also see something like the following which is also accurate. The degree of error when measuring IQ is about the same if one were to shift from 10 – 20 µg/dl.

Counter argument What is called a small effect has tremendous consequences. Moving the distribution of average IQ among American children down by 3 points would lead to an increase of approximately 2 million children classified as mentally retarded as defined by IQ below 70.

d. 6 3 for each argument

Toxic soup toxins tend to co-occur, rarely exposed to a single toxin

Nonspecific effects more than one toxin can produce the same outcome (e.g. both lead

and mercury damage IQ.

No unexposed controls for some toxins like lead, everyone has some body burden of lead

Subclinical effects are subtle and can be challenging to detect. They occur at very low levels,

far below those necessary to cause organic damage, detectable upon medical evaluation.

Reliance on animal testing to conduct true experiments raises ethical challenges and concern

about generalizability of results to humans

Lag effects exposures may not result in impacts until later time period

Critical period for many toxins exposure at different ages (state of maturation) results in

differential impacts, including in some cases, no effects.

Gene x environment interactions emerging evidence that some toxins that have weak or

no associations with outcomes in the overall population, are associated with adverse

effects among subset of individuals with genetic vulnerabilities

Environmental justice since toxic exposure is associated with SES as well as ethnicity, difficult

to tease apart toxin effects form these and other sociodemographic characteristics. Some

students may express this differently talking about self-selection or confounding with SES.

e. 10 4 for experiment; 6 for discussion of how it refutes each of problems in part d.

Need a true experiment with controlled exposure to lead and assessment of IQ. Need to

mention random assignment to different levels of lead exposure.

Note: True experiment needs random assignment of different levels of treatment, which means ensure that each participant has the same opportunity to be assigned to any given group. Twin experiment is a good strategy to control factors. However, it is also necessary to mention that each pair of twins is randomly assigned to different groups.

Then discuss how the experiment refutes the subset of three problems raised in part d.

QUESTION 2. Grader: Youngsoo

a. This photo shows part of the experimental setting of an experiment Calhoun conducted on animal behavior and crowding. What is the relation between this experiment, by Calhoun, and Malthus’ theory of carrying capacity? Explain whether the results support or contradict Malthus’ theory and explain why.

Sub rubrics - 12 points

|For explaining Malthus’ theory |

|3 |Explanation of Malthus’ theory + rationale (2) |

|3 |Explanation of Calhoun experiment + rationale (2) |

|Link to Calhoun research |

|3 |Contradict |

|3 |Rationale |

Answer key or example answers

This experiment found results that contradict Malthus’ theory of carrying capacity. Malthus argued that the primary check on population growth was the amount of resources necessary to sustain a population. For instance food and water. Once there are more animals/people than can be supported by the land, there will be a population crash accompanied by starvation, disease, and war/conflict. Calhoun provided the rats in his study all of the food and water that they needed. Yet they still experienced a population crash. Calhoun argued that it was crowding rather than resource depletion that led to the crash.

Example answers) Calhoun's experiments looked at how rats and their social structure functioned under crowding by raising rats in a barn, keeping them at a relatively constant population, and examining how they were affected. He provided them with enough resources (food and water) to physically survive in these conditions, but ultimately he observed that under crowded conditions, the rats' behavior and society began to fall apart due to the fact that they mentally could not live in such conditions, leading to a behavioral sink and population collapse. This contrasts with Malthus' theory of carrying capacity, which argues that a given area (the barn loft of the rats) has a limited/given amount of resources that determine how many rats can be supported and live in the area (the carrying capacity). The population typically hovers around this carrying capacity size, since if it gets too big, rats will start to die because there aren't enough resources, and if it's too small, the rat population will grow because of decreased competition. Theoretically, with Malthus' theory, the rat population should have stayed about the same in number, since Calhoun gave them a certain amount of resources to ensure their population stayed at a specific carrying capacity. However, because Malthus did not account for how animal behavior would affect population size, the rat population collapsed because their society could not function under such conditions.

b. Describe two different examples of human data covered in class or readings that show similar behavioral responses to crowding as uncovered in the Calhoun experiment.

Sub rubrics - 4 points

|Example 1 |

|1 |Example yes / no |

|1 |Detailed Rationale (from class or readings) |

|Example 2 |

|1 |Example yes / no |

|1 |Detailed Rationale (from class or readings) |

Answer key or example answers

Calhoun found evidence of elevated aggression as well as social withdrawal. He also found evidence that maternal rats did not take good care of their young. Finally he found evidence of elevated physiological stress.

Example answers) One example of human behavior that we discussed in lecture is that under crowded living conditions (high internal density), children tend to be more aggressive. This is especially seen in young boys, who become much more aggressive, whereas girls actually tend to become more withdrawn. Another example of human behavior is how college students are affected by crowded dorm life. Because crowding can lead to too many unwanted social interactions, one study found that this led college students to not only be more withdrawn, but also to shrink away from social support network, which carried over to life outside of the dorm. Specifically, the study found that these students were less likely to accept help from human supports, as evidenced by the fact that when they performed poorly on a writing assignment and were offered help by a confederate, they were much less likely to decline it.

Both of these examples connect to Calhoun's experiments with the rats, when he found that rat behavior declined so much under these crowded conditions that they isolated themselves, withdrawing from other rats, and also became much more aggressive. Overall, the poor behavior of the rats lead to a behavioral sink where all the laws of their society were abandoned.

c. Using what you know about crowding from human studies, describe two additional measures you would add to Calhoun’s experiment. For each measure:

i. Explain what you would expect to find with the measure.

ii. Draw upon prior research/theory to substantiate your arguments.

Sub rubrics - 9 points

|Measure 1 |

|1 |Measure yes / no |

|1 |Expected outcomes |

|2 |Prior research/theory (insufficient explanation -1.0) |

|Measure 2 |

|1 |Measure yes / no |

|1 |Expected outcomes |

|2 |Prior research/theory (insufficient explanation -1.0) |

| |

|1 |Defaulting point |

Answer key or example answers

Some measures of psychological distress or mental health problems. I would expect to see these elevated among crowded rats given research indicating that persons living under more crowded conditions have greater distress. Rates of infection are higher among crowded prisoners so could measure infection levels in rats. Human beings have elevated blood pressure [stress hormones] in more crowded living environments or when dealing with traffic congestion. Crowded rats would be expected to exhibit higher levels of these biomarkers of stress. Cognitive performance such as grades suffers among crowded children. We also know they are more distracted (less time on task) in more crowded classrooms. Thus could assess rat attention or some aspect of cognitive performance.

Example answers)

Two additional measures to add to Calhoun's experiment would be:

- Checking blood pressure or other such physiological signs

- Checking infection rate

We would see the following findings:

- Blood pressure: We would expect to see an increase in blood pressure as the population grows and there is higher crowding.

- Infection/Illness rate: We expect to see higher infection rates as there is more crowding and infection is easier in crowded, internally dense spaces.

Research/theory:

- There was a study done on college students that demonstrated that when there was a higher internal density (i.e, more people/room), students had higher systolic and diastolic blood pressure. This directly correlates to the expected finding of higher blood pressure as the population grows in Calhoun's experiment.

- In a study in Atlanta's Penitentiary, the results showed that higher internal density meant a higher # of illnesses. This meant that there was a direct correlation of internal density with infections or illness complaints. This aligns well with our expected finding of higher # of infections or illnesses with higher crowding in Calhoun's experiment.

QUESTION 3. Grader: Jasmine

A. Sub Rubrics -​--​4pts

1Reason 1: importance of the distinction between coping or adapting and the costs of coping/adaptation

1 Reason 2: importance of the distinction between coping or adapting and the costs of coping/adaptation

2 Correctly explain how Dubos’ theory of the paradox of adaptability relates to reasons

Students who struggled with this question compared coping vs. adapting. The question asked for a comparison of the costs of coping/adaptation vs. coping/ adaptation.

Example answers

Coping is typically seen in positive terms as something that enables human beings to manage demands or problems better. Similarly adaptation has a positive connotation in the sense that we are getting used to something or adjusting well. But there appears to be an underbelly to coping or adapting to demands or threats. Namely that these coping processes can themselves lead to some adverse outcomes.

Another distinction between coping and the cost of coping is temporal. Coping or adapting may be advantageous in the short run but in the long term lead to adverse consequences. We can tolerate the short term insult but if we continue to be exposed to suboptimal conditions, over time this can cause pathology.

Although coping or adaptation may benefit the individual or subsets of individuals, for the species or larger, global community it can bear adverse consequences. Energy use is a good example.

Each of these distinctions (unintended, negative consequences of coping; short vs. longterm consequences; personal/individual versus species benefits) fits well with Dubos’ concept of the paradox of adaptability. The first distinction fits with Dubos’ idea that vast capabilities of human beings to adapt and adjust to their environment while adaptive, can also create negative outcomes. Wide ranging capability to adapt or adjust means we can tolerate as a species an enormous range of environmental conditions and still survive. But this very adaptability also means we are able and willing to live under conditions that are not healthy for us and degrade our quality of life.

Short term advantages or benefits can follow successful coping or adaptation, but this can eventually lead to problems since it means we may continue to be exposed to adverse conditions that harm us over the long run. This illustrates the paradox of adaptability because while useful to be able to tolerate adverse conditions, if we don’t eventually do something about the conditions, it will harm us.

What may be beneficial for the individual or a group of individuals but harmful to others also fits with Dubos paradox. Adaptability by individuals may be maladaptive for the species. I good example of this is use of fossil fuels for energy. It enables some people to be more productive/efficient but harms the global climate which then harms all of us.

B. Sub Rubrics --​-​12pts

4 Noise

evidence from the course that indicates a cost of coping (2)

explain what individuals are doing to cope with each of the environmental stressors

(1)

Explain why it appears to have a cost (1)

4 Crowding

evidence from the course that indicates a cost of coping (2)

explain what individuals are doing to cope with each of the environmental stressors

(1)

Explain why it appears to have a cost (1)

4 Air Pollution

evidence from the course that indicates a cost of coping (2)

explain what individuals are doing to cope with each of the environmental stressors(1)

Explain why it appears to have a cost (1)

Example answers

Noise​– children living under noisy conditions appear to adapt/cope with the noise by learning to tune out/ignore auditory stimuli. This has a cost of reduced speech perception [deficits in auditory discrimination]. Since speech perception [auditory discrimination] is an essential building block of reading acquisition, this has a cost of delayed reading acquisition.

Another cost of coping with noise is teachers stop talking when a noisy train or airplane goes by. This adaptation however means lost teaching time leading to diminished academic achievement by students.

Crowding ​– many individuals cope with crowding by reducing social interaction. This often takes the form of social withdrawal. A cost of this is diminished social support. When offered social support when needed in a laboratory study, students from more crowded housing were less receptive to the offer. In a study of crowded housing in India, adults living in more crowded homes, had less social support.

Air pollution​People from Northern Canada react more negatively physiologically to high levels of ozone, a toxin in photochemical smog, in comparison to residents of Los Angeles. This tolerance means they have fewer respiratory problems breathing the more polluted air. The

cost of this however is that since they experience less discomfort, they then are less likely to

engage in preventive behaviors or to pressure for environmental regulations to reduce air pollution.

Students migrating to Southern California from unpolluted areas were more aware and

concerned about air pollution in their new environment in comparison to students who had migrated from areas with pollution (e.g. Honolulu vs. Denver; Phoenix vs. New York). The same migrants without prior pollution were also more sensitive to visual cues of pollution in photographs. The costs of this adaptation to smog is since they are less aware, likely less

concerned and willing to do things to either protect themselves from smog or pressure authorities to regulate emissions which produce the smog.

C. ​Sub Rubrics ---​4pts

2 .Explain Darwinian medicine

2 Explain how it relates to an answer in par b

Example answers

Darwinian medicine argues that a major contributor to ill health is modern lifestyle or living in economically, developed societies. Stress created by demands of modern life is the major contributor to disease for those living in Western, economically developed societies. Each of the above examples of costs of coping is consistent with this idea because modern life in economically developed societies often leads to greater amounts of noise, crowding, and pollution. But the strategies we use to cope with each of these environmental stressors as indicated above has serious, negative side effects that compromise health and wellbeing.

D. ​Sub Rubrics --​-​5 pts

1 Succinct and clear behavioral or performance guideline

1 Define the primary HER process your guideline reflects

1 Describe in terms of that HER processes, the rationale for the guideline

1 Comment about how people with different social identities might be affected differently by your guideline (note: this is an example of person X environment interaction) or explain why you think the guideline is likely to apply similarly to most people, i.e.., the guideline is likely universal..

1 Draw how to implement the guideline (your sketch needs to make sense; it does not need to be beautiful).

A lot of students struggled with this question. The question specifically asked for a design guideline. That meant answers needed to relate to design / physical space. A design guideline is not a policy proposal or a lesson plan for a class.

Example answers

Reduce social withdrawal under crowded conditions by providing more opportunities to regulate social interaction.

HER Process crowding which occurs when we have too much unwanted social interaction. [Alternatively the HER process could be privacy – the dynamic balance between achieved and desired levels of social interaction]

If we can provide more opportunities to regulate social interaction then less social withdrawal will be necessary when it is crowded.

Illustrations: showing more architectural depth; use of partitions to foster reduction in overload; residence as single dwelling rather than in multi dwelling complex

Minimize tuning out or ignoring speech and meaningful auditory content under noisy conditions.

HER Process noise, too much unwanted sound [high levels of sound intensity]

Interrupting the tuning out process would reduce negative cost of deficits in reading acquisition.

Illustrations: device/technology to block noise that you can control; place to temporarily remove yourself from the noise so instead of ignoring it, you temporarily escape; exposure to reminders of noise presence and its potential harm

Provide cues to maintain awareness/saliency of pollution.

HER Process: environmental stress, balance between demands and coping resources

Since people become less aware due to desensitization, by interrupting this process, people would remain aware of pollution.

Illustrations: feedback about current pollution exposure and/or impacts on the individual; visual cues showing levels of pollution (e.g. pollution thermometer); experiences with dramatic fluctuations of pollution levels so people experience clean/dirty in close proximity.

QUESTION 4 Grader: Gary

4. 4

a. The metaphor the eye is like a camera implies that vision works by simply activating sensors with energy that then produce an image. The patterns of sensory stimulation produce what we perceive. This process is passive with no interaction with the individual’s experiences or expectations about what she or he sees. Perception as a constructive process argues the opposite position claiming that we perceive things as a function of the sensory stimulation that reaches us, but we integrate that information with experience and expectations. This process is dynamic.

b. 4

Cities are embedded within states and this is how we represent information about cities. This hierarchical organization is an example of a schema-an organization framework or set of expectations we bring to the experience of perceiving the environment. Schemata are a good example of a constructive process because what we see and remember about information is affected by schemata. We take in the information but in terms of pre-existing biases or expectations about how things are supposed to look or in this case be located.

c. 6 4 for principle and why constructive; 2 for own illustration

Good figure; whole figure; closure. This Gestalt principle means we will organize and experience information in terms of whole units that we already know and understand. We see the horizontal lines in this image as letters of the alphabet. Proximity is incorrect and was -2. The whole is greater than the sum of the parts (pragnatz) was given -1 since this is not a Gestalt principle/law, reflecting the overall concept of Gestalt.

Drawing: needs to illustrate bits of information organized into some coherent figure or whole object. Drawings that simply spelled out another word or abbreviation similar to the test questions did not receive credit (-2).

d. 11 5 for hypothetical data (2) and explanation why constructive (3)

6 for person x environment interaction data (2) and explanation (4)

The various examples include: Bambuti who live in a rain forest perceive objects across the distance as larger (in front) and smaller (in back) whereas most people see objects close and farther away. Because the Bambuti live in a rain forest, they have little experience seeing thing across the horizon in the distance. The lack experience of seeing things close and far away.

The Muller Lyer illusion (lines with feathers tilted outward away from the center of the line vs. inward towards the center of the line). Most people perceive the line as longer when shown with inward feathers. However people with little or not experience of a carpentered world (objects that have corners or recessed edges) such as Zulu do not experience the illusion. The process of seeing protruding surfaces (edge) as closer and receding surfaces (corner) as farther away, distorts or judgment of sizes when displayed as closer or further away because of the feathers.

Asian individuals see background material in more detail than Westerners. Whereas material in the foreground is perceived similarly. Fish and other materials in an underwater scene; descriptions of scenes with objects and background material; illusion with balls of same size embedded in different backgrounds. Asians experience the illusion more strongly because the context has more impact.

Reproduce line length exactly or in terms of proportion of its length with respect to surrounding object. Westerners do former task better and Asians the latter.

Show two scenes sequentially and decide if second scene is identical to the first one (change blindness). Make changes in foreground material or background material. Both Asian and Westerners similar in recognizing changes in foreground but Asian individuals better at perceiving shifts in background material. In all of these examples, people from Asian cultures have learned to pay more attention to context and not prioritize the focal or target stimulus over the background.

i. Need to present data from one of these studies that reflects a cultural difference. In each case the data support environmental perception as a constructive process because people with different histories/experiences or cultural backgrounds see the exact same environmental information in different ways.

ii. Now introduce some environmental change and produce a different pattern of impacts for one culture vs. another. Note: that the change blindness example already indicates person x environment interaction since changes in environment have differential impacts as function of cultural background.

Many people lost -2 points for part ii. because they described the logic of a person x environment interaction but did not have two different environmental exposures. The reason the change blindness example works for both part i. and part ii. is because there is a personal characteristic (culture or ethnicity) and an environmental manipulation or change (background object vs. foreground object). Note: that saying one group sees the background object and one does not, does not illustrate person x environment interaction. There is only one environmental condition: background object.

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