Fix It Dr. Cheng Is Interested in Whether People Who Are Sleep

question 6

Essay

Fix It
Dr. Cheng is interested in whether people who are sleep deprived are resistant to classical conditioning. He hypothesizes that people who have been awake for an extended period will exhibit impaired learning of an association between an electrical shock and a specific geometric shape. Although he's heard that some people have reported skin irritation from the shocks in past studies, Dr. Cheng is concerned that too little shock won't be sufficient to produce a classically conditioned fear response. As such, he decides a high electrical shock is warranted despite the IRB's request to reduce it to a lower voltage. After obtaining a convenience sample of 20 healthy adult volunteers, Dr. Cheng divides them into an experimental group (n = 11) and control group (n = 9) based on their sex. He asks the experimental group to come to the lab on Friday at 9:00 a.m. and the research assistants will make sure they remain awake for 24 hours. At 9:00 a.m. on Saturday the control group, who has reportedly had a good night's rest, will arrive at the lab.
Since Dr. Cheng is interested in the brain's response to fear, he examines peoples' brain activity in an fMRI scanner during a fearful event. He's found that fear leads to changes in the activity of the amygdala, the brain's fear center.
The control participants come to the lab at 9:00 a.m. on Saturday, at which time Dr. Cheng puts all 20 participants in fMRI scanners to begin the classical conditioning protocol. The protocol is identical for all participants. An electrode is attached to the participants' ankle. While in the scanner the participants are shown 15 geometric shapes that differ in shape (i.e., circle, square, and triangle) and color (i.e., red, green, blue). Immediately before the red circle is presented the participants receive a painful shock. The shock does not occur prior to the presentation of any other shape.
Dr. Cheng believes all of his participants will learn to be fearful of the red circle and that the activity in the amygdala will provide evidence that classical conditioning has occurred, but that people who are sleep deprived will not learn this association as quickly as those who are well rested. To determine if this is true, he plans to compare the arithmetic average amygdala activity of the sleep-deprived participants to the arithmetic average amygdala activity of the well-rested participants.
Do any ethical issues exist in this study? What do you think of how Dr. Cheng assigned participants to the treatment conditions and what impact does this method of assignment have on the study? What are the problems with the way Dr. Cheng proposes to analyze the data? Fix it!

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Definitions:

Extraverted

Characterized by a preference for social interactions and high levels of energy when engaging with others.

Normative-stage Models

Psychological theories that describe human development as occurring in fixed stages, each characterized by specific norms or behaviors.

Timing-of-events Models

Analytical frameworks that emphasize the significance of when events occur in life, affecting individuals' development and life outcomes.

Trait Models

Theories that attempt to explain personality as composed of a number of consistent, measurable traits or characteristics.